The complete DIY Sump workshop!

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akunochi

Mr. Reckless
Joined
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Disclaimer- I am still adding to this for pictures, but the info is here.

DIY Sump build Workshop

Ok there have been a lot of threads lately regarding sumps, their setup and uses. I hope this will be a thourough guide to sump selection and construction from planning to use.

Now there are a million different ways to build a sump. Some are rimless, some are glass tanks with baffles, and some have a euro style brace on the top. A great resource to see many different sump styles is Melev's reef.

A couple key things to take into consideration when designing a sump are the following:

• Size available under your stand: I prefer to leave some extra room for storage, media, reactors etc.

• Dimensions needed for your equipment:

o Your return section needs to fit your return pump or be positioned in a matter that allows placement of an external return pump. As well as be as large as possible since this will be where evaporation occurs in your system.
o Your Skimmer section: Allow room here for your skimmer, probe holders, and the inlet plumbing. You may also need to take in consideration water level and a skimmer stand.
o Refugium: This will be a safe haven for your copepods/ampipods to reproduce as well as macro algae to grow. Obviously the larger the section the better as more stock can fit in here.

• Placement of your sump under the stand: This is often over looked. How will I get my new custom sump under my stand. If the tank is new then you can usually use the larger opening found at the back of a stand. If the system is running then you will need look at other means. I have removed the uprights in many stands located at the front. You can use a floor jack to support the tank while this is removed and also assist in raising it up enough to set it back into place. While the upright is out it is an ideal time to modify it to be a removable piece on your stand for future upgrades or sump access.

Ok let's get started!

Part one: You've sat back and figured out the maximum size sump you can fit. I am only referring to outside dimensions at this point. We will address baffling a little later. The only concern with baffling at this point is that the overall length of the sump will still allow your equipment to fit after baffles are added.

Now we need to calculate our cut sheet to take to the acrylic shop or do our own cuts. So how do we do this? It's pretty straight forward.

First take your desired dimensions. In this example we'll look at a 48"x20"x16" rimless sump constructed of 1/4" acrylic.

<insert image here>
Ok start at the bottom panel. The bottom pane will be the overall dimensions of your sump. In this case we need 1 piece that is 48x20.

Next we look at our long panels. We will need two of these panels. These panels will be the length of the sump and the height of the sump walls we need. Knowing that we now know we need 2 panels cut at: 48x15 3/4"

Now let's address the end panels. Because we want all the panels to sit on top of the bottom pane we need to consider the thickness of material here. First we know our height already. 15 ¾ ". This is the same as the first two panels we cut. The width is calculated by taking the desired width of the sump minus the thickness of material times 2. Why? Because the end panes will sit in between the two long panels we need to subtract the thickness of the panels. This gives us a width of 19 ½" We got that by taking the desired width of 20" and subtracting the material thickness of each pane it sits between. In a formula it would look like this

Desired width – (Material thickness used x2)

This will leave us with a final cut for two end panes at 19 ½ x 15 ¾"

Next let's address the baffles used inside. You want your baffles to be high enough to maximize water volume in the sump while still allowing the sump to hold any back flow from the Display Tank in case of a power outage. So first let's do some calculations. Using any of the available aquarium volume calculators we'll do the following.

Display tank is a 125 gallon tank: The dimensions for a standard 125 are 72" x 18" x 21". Your return outlets are sitting 2 inches below the water line without another form of break siphon. So we need to calculate how many gallons of water 72x18x2 is. Basically the length and width of the tank is used and the height is the depth of water lost before a siphon break occurs.

Okay we now know that a water loss of 11.2 gallons will be transferred to the sump in case of a power loss. So let's figure out how much space we need to leave in the sump to handle this extra water.

If our sump is 48x20 then start at 1 inch and start calculating water volume until you find the depth that will give you at least 11.2 gallons.

Okay we found that if we leave 3 inches of room in the sump it will hold 12.5 gallons. So let's put it all together.

We have a 48x20x16" sump that needs at least 3 inches to hold excess water in case of a power outage. That means at an absolute maximum our baffles can be 13". I say leave a little extra so…..
We need 4 baffles in this sump design 3 separate the skimmer and return section and 1 separates the fuge from the return for this design. Now let's get our cuts.

We need 3 baffles cut at 12" x 19 ½ inches. This is once again the width of 20 minus the material thickness x2. The 12" is out baffle height.

We also need 1 baffle cut at 13"x 19 /12". This one separates the fuge from the return. Why the extra 1"? If we cut this baffle at the same height as the previous ones (12") then the fuge and return would technically be one chamber as the water level would be just over this baffle.

OK so now we have all out cuts figured out….let's figure out how much acrylic that is.

Step 2 calculating the acrylic sheets needed.

• The typical sheet of acrylic is the same as plywood 4'x8'

Laying the cuts out on a sheet we can see that out of one full sheet we can get:
• Bottom Pane
• Both Side Panes
• Both End Panes
• All 3 regular baffles.

For the last baffle we will need to move to another sheet. Most shops will sell you a partial sheet or have scrap you can buy for the final baffle. Normally scrap is sold by weight.

Scrap or additional ¼ sheet
• Remaining baffle for the fuge

Okay we have all the acrylic cut!

Next Segment ASSEMBLY PREP!
 
Ok Assembly Prep:

Welcome back! Ok we are ready for assembly. Once again there are several ways to do this just like in all reef keeping things. Let's start by looking at materials we'll need.

You should already have all your acrylic panels cut to size.

You will need:

Weldon 4 (preferred) or Weldon 3.
693-weldon4.jpg

Bottle Applicators for the Weldon.
410803Y2GJL._SL500_SS100_.gif

Painters tape
img_4_blue_tapes.jpg

Clamps
ratchet_clamp.jpg

Quick Squares with the corner cut off
speed_squares.jpg

Acupuncture needles or a thin guitar string
shims_n_pins.jpg

Wood Shims
Wood-Shims.jpg

I know it is boring but I want to talk about a couple of the materials above and their uses.

First up is Weldon. Why is 4 preferred over 3? Weldon 4 and 3 are both of a water consistency and quick to set. The advantage over Weldon 4 is that it is slightly slower to set and gives you more working time. The problem is Weldon 4 can be hard to find and requires a hazardous material license to ship. Weldon 3 is more commonly found in your acrylic shops, but has a working time of 60 seconds.

Bottle Applicator for the Weldon: These are just little plastic squeeze bottles with a needle tip applicator. Buy at least 3 of these more if your project is large. The needle gets clogged and there is nothing in this world small enough to run through it. What you can do is use a bic lighter to heat the needle and unclog it, but this only works a couple of times.

Painters tape: This tape will be used to "Clamp" panels together and help hold things in place. It is great because of it's no residue properties.

Clamps: Clamps are your life blood on a project like this. Preferred are ones with one handed operation and padded jaws. These might not be available in the size you need though. A nice cheap one for anything over 48" can be found at harbor freight for 17.99. Just search for bar clamp and your will find 60" models. Wrap the jaws in painters tape to add padding.

Quick Squares: Found at any hardware store these are the plastic triangle squares. You want to remove the inside corner because it would be in contact with your seam otherwise and become a permanent part of your sump!

Acupuncture needles or guitar string: These are needed to create a small gap between the panels while applying the Weldon. They allow the chemical to spread into the joint and soften up the material prior to joining.

Wood Shims: These are used to level your bottom pane and apply a little extra pressure to the joint.

On to the prep!
First let's dry fit all the outside panels.

• Place your bottom pane on a solid level surface and attach painters tape under it with sticky side up and tags hanging out (So you can fold it up and attach the bottom pane to the side panels)


• Align one of your long panels on the bottom pane and square the edges (approximate) then fold the tape up to help hold it in place.

• Work clockwise or counter clockwise and repeat the process using painters tape to attach the upright panels to each other at the corners.

• Once all upright panels are up step back and admire your new sump and it all fits together nicely. If any panel was mis-cut then address it now with your acrylic vendor.

• Okay take a sharpie and number each panel 1-4 and put the corresponding number on the bottom pane as well. This will allow you to place panel 1 on the panel 1 side where you dry fit it. This can be a life saver if the wife comes in and tell you to get your fish stuff off her table!

• Okay now take it all apart! Get a beverage of your choice and prepare for no going back.


Now the MAIN EVENT! Organization is your friend as well as an extra set of hands if you can drag a friend over.

• Take all your acrylic panels and remove a 1 inch strip of the protective plastic on all four sides on both sides of the panel.

• Place your bottom pane on your work area again with fresh tape applied to the bottom and sticking out sticky side up again.

• Place the wood shims just under the panel in between the tape strips ~ ever 6" and re-verify level.


• Lay your panels out on the appropriate side of the bottom pane in the order you numbered them.

• Cut your guitar string or lay your acupuncture needles and lay them out on each side in an easy to reach area.
needle1.jpg


• Grab your clamps and put them somewhere easy to access.

• Place your plastic squares on the bottom pane facing toward the panel you are going to be working on first.

• Fill your applicator bottle with the Weldon of choice (3 or 4)

• Double and triple check everything! Once you start it is going to go fast!


ASSEMBLY

Ok you've made it this far and the next step goes by quick.

• Take your guitar string/ needles and place them every 8" along bottom pane where you will be working first.

• Take your first pane and line square it to the corners and then square it vertically.

• Fold the painters tape up to help hold this panel vertically square.

• Apply your clamps ever so slightly to the panel and bottom pane. edge of table. All wobbly? It'll get easier as you add panels.

• Now run a constant steady stream of Weldon into the joint chasing out any bubbles.

• Wait a couple seconds and then remove the guitar string/ needles and tighten the clamps to hold the panel in place.

• Re-verify all your squares.

• Slightly push the wood shims in to add pressure to the joint.

• Let the Weldon set.

• Moving in a clockwise or counterclockwise direction repeat the process for your next panel.

• Once you have 2 panels jointed to the bottom apply a bead of Weldon in the vertical joint and clamp them together.

• Repeat this process until you have a nice box made.
 
BAFFLES

Okay so now you have a box! Congrats…it almost looks like a rimless aquarium huh…lol We need to add the baffles so it becomes a sump.

• The first step is to remove the protective plastic from the inside of your sump.

• Next trim the plastic like you did for the main panels 1" around the edges. On the 3 bubble trap baffles completely remove the plastic from one side.

• Measure the distance on the skimmer side you want to the first baffle. Measure on both side and mark it so you make a nice straight baffle.

• Slide the baffle into the sump at this location and dry fit it. Does it fit nice and snug?

• Place the needles/guitar string in between the baffle and the bottom pane.

• Run a bead of Weldon into the joint and then remove the guitar strings.

• Verify vertical square using your plastic squares

• Apply downward pressure to the baffle to get a nice solid joint.

• Now turn the sump on its side and run a bead of Weldon in between the baffle and side wall. Place a weight on top of the side wall facing the ceiling to apply downward pressure.

• Let set, turn the sump over and repeat for the other side.

• Move to the next baffle which is your raise baffle.

• Leave the sump on its side and grab a couple of 1-2" pieces of wood (I use a 1x1)

• Use one piece to get a uniform distance in between the last baffle and this one and the other in between the bottom pane of the sump and the baffle to uniformly raise it off the bottom.

• Run a Weldon bead into the joint between this second baffle and the side wall. Then place a weight to apply downward pressure

• Turn the sump over and repeat.

• Remove the plastic cover on this panel before moving on….

• Remove your wood spacers.

• For the final baffle place your wood spacer in and slide the 3rd baffle in place.

• Run a bead of Weldon into the joint between the baffle and the bottom pane of the sump.

• Turn the sump on its side and run a bead of Weldon between the baffle and the wall of the sump.

• Turn the sump over and repeat.

• Remove the wood.


Refugium baffle

• Go to the other side of the tank and measure in on both sides the distance you want this baffle to sit.
• Place the baffle in and using Weldon secure all 3 sides as before.

You now have a sump with a skimmer section, center return section and refugium section.

Wait at least 24 hours and then water test. During the water test fill the skimmer section and ensure water only travels up and over the first baffle, under the second and finally over the third….then stop!

Move your hose to the refugium section and begin filling this up. No water should leave the section until it goes over the baffle. You should now have a full skimmer, baffle and fuge section with an empty return section in between. Finally fill the return section.

Doing this will let you visibly see if you didn't get a good bottom seal on any baffle. If the return section is already full then you will be unable to see if the fuge baffle is doing its job.

Let the sump sit full for 24 hours to see if any seams are leaking. If they are not leaking you are done. Congratulations……What? You have a small leak? Don't worry it isn't a wasted project.

Go and get yourself some Weldon 16. This has a much thicker syrupy consistency. Empty and dry your sump taking not of where your leaks were. Now run a bead of Weldon 16 into that area preferably with that area facing down so the Weldon will run into the joint. Wait 24 hours and repeat your leak tests.

Any Questions? Good. Pictures will follow and be placed appropriately into this article.
 
Hey Seth, NICE BUILD THREAD. Its all in the details, and well noted. Going to be a sweet sump setup to go with your NEW tank :gossip:

Cheers, Todd
 
This is great, looking forward to pics. Could this same technique be applied to glass? I was leaning towards glass being it's a lot cheaper. What would be the benefits of using acrylic over glass?
 
10g nano...lucky for you I am custom building my glass tank too. I will do a workshop on that one as well....

Benefits for glass vs acrylic can be found all over, but for cliff notes.

Acrylic:

pros: lightweight and clear. Easy to cut and drill

cons: scratches easy

Glass: scratch resistant...looks better (IMO)


Todd,

Thanks I'll get some pics up soon.
 
Very nice.
Also very well detailed. You have made it very clear on the step by step directions. Looking forward to more.
 
Looks GREAT Seth, so clean and shiny (for now) Once again nice build thread dude

Cheers, Todd
 
I'd like to add a little to this. The above assembly process (order of panels) will cause weak corners. Weldon should only be used on a horizontal to the ground surface. A completed joint should be free of all bubbles clear when dry but should also have what looks like a tiny bead (squeeze out) of acrylic all the way down the seam on both sides. Never try to solvent weld two sides of a single panel at once. The easiest way to assemble a rectangle tank is to lay the face (the front) of the tank on a flat surface. Add both ends and apply weight across them usually with some boards and weights. Then lay the back on a flat surface and install the front with sides on top of the back and use weights until dry. Now you have a rectangle with open top and bottom. Set the bottom on a flat surface then set the rectangle on the bottom, apply your weldon and add weights. Notice you are always weighing downward. Its also much easier to oversize the panels especially the bottom and flush trim it to the sides after you are all done.

In the above applying two sides to the bottom first will not allow the corner where the two sides come together to be weighted because its already stuck to the bottom. Meaning the lower corners are going to be extremely weak. When you solvent weld you are softening the acrylic and mixing the acrylic together in an attempt to make a single piece. The trick to not plugging up bottle needles is to not stop and not squeeze the bottle. If you squeeze the bottle and let go it sucks in melted acrylic. If your needle is so small you have to squeeze then just keep the needle moving until you run off an edge before releasing pressure. To avoid having to squeeze the bottle only use half of it. Use a pen and mark a spot half way down the bottle and poke a pin hole at this spot. Only fill the bottle with enough solvent to do a single seam. When you tip the bottle keep the pen mark you made up so as not to drip on the acrylic. The solvent will flow real easy out the needle. If it flows a little fast put your thumb over the hole.

Hope this makes sense.
Don
 
A completed joint should be free of all bubbles clear when dry but should also have what looks like a tiny bead (squeeze out) of acrylic all the way down the seam on both sides. Don

I have a beat tank I am rehabbing. I added 1/4 squares on the perimeter as you suggested and I get bubbles. What causes this?

I sealed a hole in the X-overflow with a plastic disk and have bubbles and neat patterns there too. I will be doin a patch in another tank that will be more visible and would like to work this out before starting. I have some issues with the weldon leaking out the bottom of the prior hole for the bulkhead with slight hazing. Do you have a trick for this?
 
Your using the wrong solvent/glue for this application. Your crazing is from your patch being exposed to too high of temperatures. Flame polishing has the same effect. That's why I don't even own a torch. If anyone needs some small pieces of cell cast acrylic, or pieces cut to size, PM me and I can give you some. Jason
 

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