Any PVC sumps out there?

[McPuff]

I've been considering building a PVC sump to replace my current 60 gal (48x18x14H) and provide extra volume (and backflow space, mostly). There have been a few people here and there that have built smaller sumps out of the sheet PVC one finds at Home Depot, etc. Wondering what experience others have had with this material.

The sump I'd build would measure 53" x 24" x 20"H which is about the max size that will fit in my space. This rules out any stock/standard size aquariums, troughs, etc. (I've searched!). So I've gotta build something myself and acrylic is way too expensive (glass is too for that matter). If I used PVC I would create some internal "ribs"/gussets and maybe do a Eurobrace of sorts. Would also include additional corner "fillers" to improve structural rigidity and bonding surface. If you've done this, here are a few questions I've got:

-What size sump did you build? Dimensions?
-How did you bond the panels together? PVC cement, heat, other?
-How much deflection do you notice?
-Any special supports, gussets, bracing? Baffles will add to overall strength for sure.

Finally, is this just a stupid idea? Should I simply build one out of plywood and pond shield/bed liner instead? Honestly, they might both cost about the same and plywood is proven. Always looking for new options though!

 

[Even Further]

One way to score a cheap DIY sump is to find a free leaking glass tank, and salvage the glass panels. I made my DIY sump from free glass that way. It was a time killer to do it, but worth it since I got my preferred sump design in the end. IMO I would not do plywood and stick with glass or plastic.

 

[Fin]

One of our local members built a nice PVC sump. This is a link to his thread (where he begins the sump) on Louisiana Reef Club

 

[McPuff]

One way to score a cheap DIY sump is to find a free leaking glass tank, and salvage the glass panels. I made my DIY sump from free glass that way. It was a time killer to do it, but worth it since I got my preferred sump design in the end. IMO I would not do plywood and stick with glass or plastic.

Salvage tanks would make for a cheap sump, I agree. But the effort involved with cutting glass (almost certainly) would outweigh the cost savings. Why would you not go with plywood? There are so many great examples of what can be done with plywood for displays, sumps, etc.

 

[McPuff]

One of our local members built a nice PVC sump. This is a link to his thread (where he begins the sump) on Louisiana Reef Club

Whoa, that is a very cool sump. And it's very close in dimension to what I would build. I'll have to see what type Home Depot carries. Do you know what he used to bond the panels? Just PVC cement? He says "epoxy" but maybe that's a generic term?

 

[Fin]

Not really sure what he used to bond the panels together. I was wondering the same thing. I believe the only thing that didn't go as planned was the clear acrylic tops. He didn't use polycarbonate and the tops warped from being over water.

 

[User1]

Only issue I could see is if it leaches anything over time. Food grade, water, vs. other. Otherwise you would treat it like any other building material and it should cut, clamp, and clue similar. I haven't looked at what size sheets those come in but if they came in 4 x 8 like a sheet of MDF or plywood then you could probably be in business. May be as simple as gluing plumbing together. Sand to rough, prime, clue, clamp, and hold in this case.

I've never considered it but may have to now.

 

[McPuff]

Only issue I could see is if it leaches anything over time. Food grade, water, vs. other. Otherwise you would treat it like any other building material and it should cut, clamp, and clue similar. I haven't looked at what size sheets those come in but if they came in 4 x 8 like a sheet of MDF or plywood then you could probably be in business. May be as simple as gluing plumbing together. Sand to rough, prime, clue, clamp, and hold in this case.

I've never considered it but may have to now.

Yes, it does come in 4 x 8' sheets. And I have read some people say they use PVC cement to bond them. Others say plastic welding. The one referenced above looks like it may have been PVC cement but possibly some other type of epoxy.

 

[reefwiser]

One would have to have an end mill to create a channel for the sheets to go down into a slot and this would have to be done on the corners also. Straight glue will not hold against the water pressure. The red lines are made by a PVC welder and a red PVC rod. I have a PVC welder from when I made my own skimmers.
Royal Exclusiv makes their sumps out of PVC.

 

[User1]

One would have to have an end mill to create a channel for the sheets to go down into a slot and this would have to be done on the corners also. Straight glue will not hold against the water pressure. The red lines are made by a PVC welder and a red PVC rod. I have a PVC welder from when I made my own skimmers.
Royal Exclusiv makes their sumps out of PVC.

Router should be able to make those channels. Or at least I would think.

 

[McPuff]

Straight glue will not hold against the water pressure.

Do you mean PVC cement? Doesn't this create a chemical bond?

 

[reefwiser]

Yes PVC cement will not do it unless you mill a slot. Try this at home take two pieces of PVC pipe put PVC cement on each end of the pipe stick it together. Now See how will the joint will hold.

 

[User1]

Yes PVC cement will not do it unless you mill a slot. Try this at home take two pieces of PVC pipe put PVC cement on each end of the pipe stick it together. Now See how will the joint will hold.

That makes sense. So just treat it like you are making a drawer. Route out all pieces connecting to include the top Euro brace and then use standard pvc primer and glue. If that is how it would be done.

What does a 4 x 8 sheet of pvc run these days and what is the thickness used? I'm guessing the main sump box has to be somewhat thick to handle the grooves/channels for the baffles or whatever you use inside the sump. If a sheet of pvc isn't crazy expensive (4x8 sheet of 3/4 thick plywood is 48 bucks in Ca at the moment just for reference) may be worth a try just to see what can be done.

 

[McPuff]

Yes PVC cement will not do it unless you mill a slot. Try this at home take two pieces of PVC pipe put PVC cement on each end of the pipe stick it together. Now See how will the joint will hold.

Yeah, totally understand... have tried it in fact and you're right. :0) Sounds like routing a trough in the bottom and top would be the way to go... maybe WITH gussets in the corners (especially vertical corners) is the way to go. That said, it seems that while the PVC sump would look really nice after all is said and done, a plywood sump might be much easier to construct. Decisions, decisions...

 

[reefwiser]

I have built plywood sumps for our local zoo. They do fine if you brace them and Epoxy coat them.
They best sump is a Rubbermaid cattle trough.

 

[User1]

I have built plywood sumps for our local zoo. They do fine if you brace them and Epoxy coat them.
They best sump is a Rubbermaid cattle trough.

These are a good choice for most but if you are working under a stand then you only have to work within the space constraints. The only other issue, may not be a big one, is managing bubble traps or such. I've thought about connecting three 24 gallon PE rectangular storage tanks, covers included, and using first one for the tanks overflow location, second unit for refugium, and third / last unit for return. Connect them each with a bean animal primary, secondary, and emergency piping, and call it a day. Tick over 100 dollars each would still be cheaper than most pre-built sumps...

 

[McPuff]

These are a good choice for most but if you are working under a stand then you only have to work within the space constraints. The only other issue, may not be a big one, is managing bubble traps or such. I've thought about connecting three 24 gallon PE rectangular storage tanks, covers included, and using first one for the tanks overflow location, second unit for refugium, and third / last unit for return. Connect them each with a bean animal primary, secondary, and emergency piping, and call it a day. Tick over 100 dollars each would still be cheaper than most pre-built sumps...

You've identified my problem in a way. I have a space constraint but it's mostly a height constraint. My drain lines come through the wall and this cannot really be changed. Therefore, I have to maintain a max height of 22" for the sump. I have tried and tried to find a ready-made trough solution but most of them are just too high. Cutting holes in them to accommodate the drain lines wouldn't make any sense as I would lose volume in the sump... and that is the primary reason I want to up-size. I wish I could make the 100 or even 150 gallon Rubbermaid work, because they are SO much cheaper and they have the bulkhead drain which would come in handy for water changes.

I have built plywood sumps for our local zoo. They do fine if you brace them and Epoxy coat them.

I'd definitely coat the inside and out of the sump. Pond Armor or Rhino liner (or similar). Corners would have gussets and I'd make a Eurobrace plus center brace. Overbuilt sump brings peace of mind. :0)

 

[reefwiser]

With all the ready made sump options out there today. The cost of building one vs making something from scratch is an issue.

 

[McPuff]

With all the ready made sump options out there today. The cost of building one vs making something from scratch is an issue.

Very true. Just haven't been able to find anything that would fit into the space I've got. Plus, I like to DIY things so it would be fun and rewarding... and I'd get exactly what I wanted.

 

[User1]

Let me preference this by saying I've not looked into cost of a 4 x 8 sheet of PVC before so no idea what a decent cost would be. However, local box store had a .375" x 48" x 8' sheet for 78 bucks. Says it is 100% PVC but not sure if that equals potable water standards, etc.

Assuming a sheet can be had for under 80 bucks one could build a sump a lot cheaper than buying something off the shelf (most over the counter sumps are over 300) even if you included hobbyist time. I'd wager supplies would come under 200 - 250 easy.