Silicone and Super glue

Two common adhesives found in the aquarium industry, but I’m not going to go over the differences and when to use them. I'm going to teach you a trick.

Silicone grease, not adhesive, is often used on O-rings and flanges, like in your RO unit.  You can find the FDA grade at most home improvement stores.  Did you a dab of silicone grease over the tip of your super glue will keep the cap from getting stuck on.  Great when you buy the huge bottles of Coral Glue to keep you from gluing the cap on before you are done with the bottle.   Happy reefing everyone.

#ecotechmarine #ijustgluedmyfingertogether

Filter socks – Pros and Cons

Filter socks are one of those items that always turn into a debate when discussed.  So what’s the big deal?  Why do people love or hate them?

There are tons of variations of socks and sock holders that make the impressions of filter sock use inconsistent between users.  Different microns, materials and how you install and remove the sock from your sump can all play into how someone feels about filter sock use.


The Bad -  low micron felt filter sock with an hang on filter sock holder.  It really doesn’t get much worse than this.  A low micron sock is basically used for polishing water and will get clogged quickly.  (refer to the post about microns for more details).  To further compound the issue, add on filter sock holders generally don’t work very well since they are designed to be universal and not to work with any one sump design.  The result is usually a mess whenever you try to change the sock and a very irritated individual.  Cleaning felt filter socks is no fun either.   Take it outside and blast it with the highest pressure water you can find then sneak it into the washing machine without the spouse noticing.  Generally, felt filter socks never really get cleaned properly.  Not only that, people with this type of setup get frustrated with the whole process that they just leave the filter sock in the sump overflowing and it becomes a nutrient factory.


The Good – The best way to use filter socks is to utilize them as a short term coarse mechanical filter.  Put them in to clean up excess food or when you are stirring up detritus during maintenance.  Use a mesh filter sock since they need just a simple rinse under the faucet to clean and never leave them in the sump more than a few days.  If you think you will use them regularly get them built into the sump.  The new waterfall style sock holders where water first drains into a separate section then cascades into the socks makes maintenance much easier and should be utilized whenever possible.

Why do we only sell heater holders in pairs?

You may have noticed that our heater holders are designed to hold two heaters.  We don’t sell a design that holds only one heater.  Why is that?

Heaters are notorious for breaking and if they get stuck on they can easily overheat and kill your tank.  The on and off switch on heaters is a piece of metal that bends with temperature.  As the temperature changes in your tank the bend in the material will change.  Depending on where you set the temperature is the position in the bend where the material completes the circuit and turns on the heater.  The problem is that connection and wire are fragile.  A simple arc will fuse that connection permanently keeping the heater on.

We have positions for two heaters on our heater holders is to help minimize the risk of a heater that gets stuck on.  The idea is to pick two smaller heaters than combined have enough wattage to heat up your tank to its desired temperature.  However, each heater on its own will not have enough power to overheat the tank if it gets stuck on.  With your powers combined... (just kidding)

It’s always a good idea to check on your heaters a few times a year and especially before the winter season.

How big of a sump do I need?

Usually the first question I will get when designing a custom sump for an individual is “how big of a sump do I need?”  Many will give the generic answer “As big as you can fit!”  This isn’t entirely a bad answer, but usually it doesn’t really help the individual that asked the question.  I like to break it down into several parts:

1.       What size is your tank?  From this we can calculate the total volume of water we the sump needs to hold during a power failure and we can estimate the sizing of equipment that needs to fit in the sump.

2.       What style of filtration setup are you planning going with? Berlin, fuge, Triton, Zeovit?  Each style has it requirements for layout that need to be considered.

3.       Estimate the space you have under your tank. This doesn’t just mean the space between the walls, but also think about all the components you plan on placing under your tank other than your sump.  ATO reservoir, reactors, dosing container, and test kits are all common items you would find under the stand and should be accounted for before setting the dimensions of the sump.

Once you have those items answered rough dimensions can start to be laid out.  Sometimes due to space constraints you may need to change the approach to filtration.  It’s best to figure this out at the beginning of the build so you can adjust rather than when your sump arrives.

If you are needing assistance with layout your custom sump you can contact us at and we would be happy to help you.

What's the difference in acrylic for my sump or tank?

Plastics – What’s the difference?

You’re looking for a custom sump or to make your own DIY sump or tank.  There’s a term you keep seeing “cell cast acrylic”.  What does that mean?

Extruded vs cast

Extruded/cast acrylic refers to the fabrication method of the acrylic.  Extruded acrylic is squeezed through a form like frosting a cake whereas cast acrylic is poured into a form.  Due to the fabrication method extruded acrylic is more pliable and “softer”.  When it comes to aquarium products extruded acrylic should be avoided as it does not have the strength to hold up to pressure vessels. i.e. aquariums and sumps.

Cast acrylic is the only type of acrylic that should be used for tanks and sumps.  Does that mean any cast acrylic will work?  Not exactly.


Domestic vs imported

We know we need cast acrylic, does that mean we can just get any cast acrylic. 


As we talked about above cast acrylic is the means in which the acrylic is created.  However, it does not refer to the makeup of the acrylic itself.  Staying on food examples, we make something in a round cake pan.  That doesn’t tell us if we made a chocolate cake, vanilla cake, or maybe we got crazy and made a shepherd pie.  

So what does this have to do with imported vs domestic acrylic?  Imported acrylic is always cheaper, but that difference in value has to come from somewhere and in this case the reduced cost is made up in the composition of the acrylic and the quality control.  Even if the acrylic is cast the makeup of the acrylic is still inferior.  Imported acrylic (Chinese and South American in this case) will be more inconsistent and act more like extruded acrylic than cast.

It has the second issue of imported acrylic is being metric.  ¼” imported acrylic is actually 5-6 mm which is almost 20% thinner than its domestic counterparts.  So just by buying imported acrylic you are getting up to 20% less product.

At Building An Obsession we only use domestic cell cast acrylic in our custom sumps and other aquarium products.  We use this for the quality of the material, consistency from sheet to sheet, and because we firmly believe in supporting jobs and the economy of the great nation we live in.


In the end those looking to do some DIY often want to just cut to the chase and ask me what they should buy.  Here are my top brands to look for and to avoid.

#1 Polyone (formerly known as Spartech) Polycast GP

For BAO sumps and products is our go to brand.  It’s a domestically made high quality cell cast acrylic.  Granted the cost is about 40% more than its imported counter parts but we feel the quality is well worth the price.


#2 Arkema PlexiG

This is a great product with both imported and domestic versions.  The domestic version is hard to find but well worth is when you can.  We only use the domestic version when necessary.  There is also a generic version of this which is not the same product.


#3 Reynolds R – Cast

Another great cell cast acrylic.  Only reason it is #3 is because it is really only used when the thickness needed is over 1”.  This is really only used for huge displays and public aquariums


The bad list

#1 Acrystar

This South American acrylic is flat out the worst acrylic we have ever seen.  It’s soft, gummy, and just plain terrible.  To make matters worse acrylic suppliers love to push this stuff due to super high margins.  They’ll make up any story to try and sell it, but avoid it at all costs.

#2 Trucast

We’ve found this material to be thin and extremely inconsistent.  We have tried to use this material for signage in the past and found up to 25% variances in thickness as well as strange particles imbedded in the material.

#3 Chemcast

Chemcast in the late 90’s to early 2000’s was a great brand with some quality material.  However, they moved the plants to China and it has been on fabricators do not use list ever since.  The material completely changed after that so be aware that some might remember the good ole days when I was still usable when referring to its usability. Acrylite followed the exact same history.  Was great in the past when it was made in the USA, but the current Chinese equivalent is not the same.

#4 Unmarked brands

This should be #1 but since there’s no real way to tell what it is we put it at 4.  Any unmarked brand in a paper or plastic masking should be avoided.  Generic is certainly not good in acrylic fabrication where knowing the material and characteristics are so important.  Suppliers will push this stuff hard so just say no.  (side bar:  there are times that brands will mask their sheets in plain paper.  We ordered a custom run of 80 sheets of a color from Polyone once and received it plain masked.  Since we knew it came straight from the factory we were ok with it.  In all other scenarios reject the sheet and get a branded one)



Ask your custom sump builder what material they use.  Look at pictures and verify if possible that they are using the best material for your aquarium project. 



If you are planning on DIY for a project start with the best material and go from there.  If you skimp on the material you will be starting the project at a disadvantage.

Reef Photography

 Photo provided by Josh Pork Sandwich Zoas

Photo provided by Josh Pork Sandwich Zoas

A friend asked for help this weekend, he had rented an expensive DSLR camera but still could not get a decent photo of his tank.  As we went through the steps I thought I might share some of my experience here so others can learn as well.  

Now I'm no professional photographer, but there are a few simple things that can help everyone.

I personally think that videos are easier to follow so I'll be posting these to our YouTube site and post brief overviews here.  

If there's a particular issue you have let me know and I'll see if I can help or maybe someone else will chime in. 

Dipping made easy

We had a great weekend with a local show in town and filled our frag transport with plenty of coral.  I thought I would share a quick trick that we use to safely and quickly dip all our coral.

Since we know the frag transport box we were using was 11 cups, all we had to do was some quick math to determine how much dip to use.  Personally, I use Bayer so 11 cups times 20 ml per cup gives us 220 ml of Bayer to add to the frag transport.  Let it sit for 5 min and we can remove all the racks simultaneously using the insert and rinse.

Using the insert to remove the coral is key here.  Bayer is nasty stuff and has all sorts of health precautions on the label.  You don't want to touch this stuff even in diluted form if possible.  This really goes for all dips since many of the commercially available dips don't even fully list all the ingredients.

If you have a frag transport with a single rack and no insert just ask us for some extra posts.  These posts can be placed in a hole of the rack prior to adding the dip then used to lift the rack out of the dip keeping you hands out of the dip.

Pests can destroy your tank so make sure to dip all your coral whether they came from a show, friends, or LFS.

Quarantine Tanks

As the industry grows and sources of fish grow so does the potential to spread deadly parasites and diseases.  Quarantining your fish is not a luxury, but a necessity.  Quarantine tanks do not need to be fancy.   A simple 10 -20 gallon tank is usually adequate with a small heater, air stone, and some type of filtration.

Hang on back filtration is easy and a reasonably affordable solution.  Sponge filters attached to the airstones work as well.  If you use carbon in the tank make sure to remove it before dosing any medications.  Don’t place any sand or rock in your QT tank.  A large diameter PVC pipe can be used to give inhabitants a place to hide if necessary.

Quarantine tanks do not need to be permanent either.  They can be stored away until you purchase a fish or coral.  If you plan on cruising the fish stores looking for a new purchase just make some water for a water change a day or so before.  If you happen to find something to buy then do a water change and use the old water to fill the quarantine.  Make sure to have an ammonia test kit on hand and test daily.  Regular water changes with your existing tank water is generally enough to keep the QT stable.

My Overflow Is Loud

One of the most common troubleshooting issues people get once they setup their tank is noise coming from their overflow.  The most common noise issues are constant gurgling or flushing noises.  Flushing noises come from downward water pressure on the drain lines causing a syphon.  Much like a toilet, syphons speed the draining effect of the pipes which drains the overflow in seconds.  As soon as the water line is below the pipes in the overflow it draws in air which breaks the syphon and causes the flushing noise. 

To combat this, the Durso, Maggie muffler and other methods were developed.  These methods introduce air into the drain pipe to prevent the syphon from ever happening.  The issue with this is it introduces the second most common noise issue, gurgling.  Gurgling often comes from the mix of air and water running through the drain pipe and exiting in the sump.  Another side effect of this is the accumulation of salt creep from the air bubble popping and misting salty air around the sump area.

Two new methods were developed that not only help with the noise found with the durso method, but also provide an emergency fall back, the Bean Animal and Herbie.  These two methods utilize a full syphon of pure water with no air.  This eliminates the gurgling noise caused by the air and increases the flow rate that can be handled by a smaller diameter pipe.  In addition, they both provide an emergency drain in case the main drain gets clogged for any reason.

If you are having issues with drain noise look into the Bean Animal and Herbie methods.  They are both quieter and safer than the durso setups and can be installed into most aquariums with at least two bulkheads.

A sump for the Triton Method

The newest kid on the block these days is the Triton Method.  People have been quick to adopt and criticize the high resolution testing and additives of this new approach calling it everything from the future of reefing to another marketing gimmick.  Unfortunately, I think many miss the point completely on this new approach with the myriad of tests and additives and fail to see that the “method” is truly about simplicity and understanding of your aquarium.

Ehsan has said it himself, the Triton Method really isn’t a method at all.  It’s just a means of understanding what is actually happening in your aquarium.  The tests break down every detail of what is happening in your tank and empower you to make the decision and appropriate changes.  You are supplied with the knowledge and you take the action to maintain or improve the environment of your tank.

What I think is also great about this method is the purity and simplicity of the filtration.  There is no requirement for specialty equipment, no need for proprietary bio material or mysterious liquid in bottles.  The mechanics are simple, an appropriately sized fuge and a skimmer.  The key here is an APPROPRIATELY SIZED refugium.  Somehow through all the marketing of widgets and gizmos, refugiums have gone by the way side.  If you find a fuge at all in your sump it’s likely to be 1-5% of your overall water volume making pretty much pointless for nutrient export.  The Triton Method recommends 10-20% of your water volume dedicated to a fuge.  A fuge is the main nutrient export, a throwback to decades ago when fuges were the norm and skimmers were just supplements to filtration, but still a tried and true method that has stood the test of time.  Julian Sprung even just spoke about this very topic at the 2014 MACNA.  Use the filtration that is easiest and most stable and spend your time understanding and enjoying what is in your tank.

Now the Triton Method is not for everyone, but if you want to start the Triton method and don’t have a fuge adding one is easy.  Simply elevate any container higher than your sump and use a small pump to push water to that container.  A simple bulkhead or uniseal will allow the water to gravity feed back to your sump.  Just remember it needs to be 10-20% of your overall water volume.

What is a micron?

Filter socks are listed by microns, but what exactly is a micron.  Microns are a unit of measurement just like inches or feet.  So just like inches or feet the smaller the micron means the smaller the opening to allow a particulate through.  Basically, higher numbers mean less filtering and smaller numbers mean more.

The most common micron socks are 400, 300, 200 and 100.  300 micron will allow more through versus a 100 micron due to the openings in the material being larger.  This also means it will clog slower, than the 200 micron or 100 micron counterpart.   100 microns are pretty small and usually clog within a day or two.  They are however a great way to polish your water a bit before company is over.  Remember, socks should be rinsed out every 2-3 days so you shouldn't pick a higher micron just so that you can leave the sock in for a week without it overflowing.


Happy reefing.

Setting up Dosing Containers

So once you have your dosing containers  and you are ready to dose your two part alk and calcium.  So how do you hook them up?


The most common way is to use a simple airline connector.  These can be found in any pet store and generally are clear.  However, I have found that after time the dosing line hose will stretch slightly causing these to fall of.  A better solution is to use a 1/4" connector for garden misting or drip irrigation.  These come with barbs on either end which do a better job of holding on to the tubing.  They take a bit more effort to install but once they are on they never come off.


Fuge or No Fuge

Whether or not to run a fuge is a huge debate that really doesn’t have a firm concise answer.  When I get asked, “should I run a fuge” or “why do some of my sumps not include a fuge,” I like to ask two questions.  What are you trying to accomplish by running a fuge and how much space do you have?

One of the most important items to sort out first is the purpose of your fuge.  Are you using it for nutrient export or are you using it as a safe haven for delicate animals and pods.  Just like sumps, fuges are not all the same and the design varies depending on the purpose.  To not have a clear direction towards nutrient export or safe haven will result in a mediocre performing fuge simply because it’s not directly designed to do what you want it to do.  Have the right tool for the right job.

Nutrient export is the most common reason people run fuges.  I’m also going to lump stability into this same category, because the design is generally the same.  Fuges designed for this purpose generally utilize macro algae to remove excess nutrients.  Here’s where most get it wrong.  Just slapping a sectioned off portion of the sump that water flows through on the way to the skimmer will not provide the proper conditions for your fuge to work properly. 

The flow rates for your skimmer versus your fuge are different.  Skimmers required a certain flow rate and water run height to perform appropriately.  There are dozens of factors that go into maximizing the performance of your skimmer.  I’ll save the flow rate discussion for another day, but generally state that skimmers are designed to work in a somewhat brisk pace of flow.  Fuges on the other hand required a much slower rate of flow.  Since the process of nutrient extraction is based on photosynthesis, the macro algae needs the time to absorb the nutrients before it is returned to the tank.  For this reason, I find it best to separate the fuge, either with a completely separate tank or in the sump and just not in the linear path of the main flow of the sump.

Consideration #2: Size.  If you enlarge the scale it is pretty easy to see 10 gallon fuge is not going to have any effect on a 500 gallon tank.  Take that same scale to a 100 gallon tank and you end up with a 2 gallon fuge.  Majority of sumps with a built in refugium have less than a 2 gallon fuge so why would this work any better.  Size the fuge appropriately for the display if your purpose is nutrient export.  15-20% should be the minimum.

As equipment obsessed as I am I still love fuges.  Every tank I run has a fuge and not a single one is built into the sump.  This gives me great flexibility in cleaning and testing out different conditions for nutrient export or housing delicate species.  If you’re looking into getting a fuge take the time to decide a reason for it and if you need some help we are always happy to chat.

Know what you are buying

I’ve noticed a strange paradigm with used tanks.  Consumers seem to be wary of buying glass aquariums checking every seam and seal, but when it comes to acrylic tanks they assume all is good because it is acrylic so it’s stronger than glass right?

In my eyes a used acrylic tank is far more risky than a glass tank.  It’s not that acrylic tanks are weaker, but there are far more individuals attempting to build acrylic tanks on their own that have no business doing so.  To further magnify the issue the average consumer is not able to identify a poorly built acrylic tank.  We have a plethora of leaky tanks and sumps that come through where the customer purchased via some forum that are obviously built wrong, but we are fabricators and we work with this on a daily basis.  What jumps out to us usually doesn’t to an average consumer.  Study up on what to look for in used acrylic tanks before you buy one.

Another paradigm I often hear is, “acrylic tanks are easier to fix than glass”.  Hardly the truth.  Due to the nature in which we use the tanks, exposing them to salt, dirt, and chemicals, acrylic tanks are often hard to repair.  Scratches may be easier to polish out, but major repairs like seam breaks are quite expensive if repairable at all.

So the next time you are thinking about purchasing a used acrylic tank, educate yourself about the tank first.  Who was the builder, how old is it, and if possible have a trusted fabricator look at it first.  Don’t get into the notion that fixes are easy and cheap.  Saving a few dollars on a cheap used tank, whether glass or acrylic, never seems like a good idea standing in a flooded living room.

Faster is not better

I like to take a different approach with my customers and spend some time talking to them when we design a custom sump for them.  Instead of rushing through and pushing a standard design onto them, generally several conversation or emails are required before settling in on a design.  From a business stand point most would view this as time wasted because many customers would be happy enough with a standard line sump.  I however find that those that seek out a custom sump generally have a story to tell or a problem to solve and listening first results in a happier customer later.


During acrylic fabrication, faster is also not better.  Other companies will boast their production volumes, touting that they were able to crank out X number of sumps or tanks before lunch.  I see these comments and cringe and here’s why.  Acrylic takes a certain amount of time to cure before it comes to full strength.  To come to 80% strength ¼” cell cast acrylic takes 24 hours to cure.  If the acrylic is thicker, then the cure time increases.  In simple terms this means once a wall is welded it should not be touched or moved for at least 24 hours.  Any movement results in a weakened joint.  So how exactly do you build a complete sump in half a day when one wall takes 24 hours to cure?


At Building An Obsession, our objective is not to crank out, but craft our sumps and tanks.  We have plenty of space to let sumps sit and play the waiting game until they are cured and ready to be moved.  Yes, this result in longer build times and less sumps made, but we feel it is absolutely mandatory for our products.  This hobby is always test of patience, so what ‘s a few more days of cure time in the grand scheme of things.

Flame Polishing - The Bad and the Ugly

Flame polishing is the technique of using a heat source, generally an open flame, to melt and thereby polish the edge of a piece of plastic.  For reefing, this is usually most applicable to sumps.   If done correctly the finished result resembles an edge that is as clear as the original acrylic.

Why is this a problem? 

Since you are melting the acrylic the stress on the material is substantial and permanent.  Often one will find that the acrylic will craze, i.e. micro fracture, after time and use.  The stress from flame polishing a welded seam generally reduces the seam strength by 50%.  One of the frequent causes of split seams we see in the shop are from sumps or tanks that have been flame polished.  To make things worse none of these are repairable.

So why if flame polishing is bad are builders and manufacturers doing it? 

Simple answer is cost.  The time to flame polish a sump or tank can be counted in seconds.  The time to properly polish a sump via the proper mechanical means is measured in minutes or hours.  If a builder gets behind on a custom sump build or the manufacturer is running behind production timelines the time savings can be significant.

Our custom sumps are never flame polished.  With all the time and care spent building our products it would be a waste to rush to finish and ruin our products by flame polishing.  So we polish all our sumps and tanks by hand.  Like all things in this hobby good things come with time and patience.



What are foam blocks for and why to BAO sumps not include them?

Foam blocks are not something you will find in any BAO custom sump or any of our standard line sumps.  When discussing custom sump design with customers we sometimes get the question of why they are not utilized, as they are accustomed to having them in their existing sump.

For starters what is a foam block?

Foam blocks in general are a large pore sponge used in between the skimmer section and return.  These are often used to prevent bubbles from entering the return can creating micro bubbles in your display.  To a lesser degree they are used for mechanical filtration.

So why do BAO sumps not include foam blocks?

Our sumps are designed to trap bubbles via a bubble trap instead of a foam block.  If designed properly a bubble trap is just as effective as a foam block at preventing micro bubbles in the display.  The catch is using a baffle system to trap bubble requires more effort and knowledge of placement than randomly throwing in a foam block. 

We also try and design our sumps to keep needed maintenance to a minimum.  Foam block tend to accumulate detritus and need to be cleaned frequently (at least twice a week).  Being that they are a porous sponge, over the long term they become harder and harder to clean and often end up leaching nitrates back into the tank.

As mechanical filtration, we find that foam blocks are often placed poorly. We find that mechanical filtration is best placed prior to the skimmer to allow removal of any larger particles.  This allows the skimmer to work more efficiently to remove the remaining organics in the water.   You will notice, however, that foam blocks are almost always placed after the skimmer.


So ditch the foam block and opt for a sump that has been designed correctly.  If you have any design questions we are always happy to chat.  With over a decade of experience we know what works and what is just marketing.

Eurobraced or Rimless Aquariums?

We often get requests for rimless tanks in acrylic, and questions about the high price after we provide a quote, so I'll take a second to explain why rimless tanks and acrylic are really not a good combination.

Acrylic does not have nearly the same strength of glass when it comes to bending.  So that means a tank made with 3/8" glass will require significantly thicker material in acrylic.   Also material thickness increases faster with the height of the tank than the length and with of the tank.  This is because the force of the water is much greater as height increases as opposed to length and width.

So what does this mean?  Simply put, if you want a rimless aquarium you should probably look to glass rather than acrylic.  The exception is frag tanks.  Because frag tanks are generally 10" or under either 1/2" or 3/8" cell cast acrylic can sometimes be used to achieve a rimless look.  Each manufacturer publishes correct thickness of acrylic depending on use, or their engineering department is available to validate usage.  Make sure your builder has access to these resources to ensure that the correct thickness of material is used.

Here at BAO, we fabricate custom tanks, frag tanks, custom sumps, auto top off reservoirs.  If you find a need for anything don't hesitate to contact us.  Our contact information is available on our Contact Us page.  We love talking with the reefing community so feel free to give us a ring.