Ply filters?

[esoxlucius]

I agree with tobias in as much that yes in can be done. But then why isn't it done more often? The cheap option of a large plastic receptacle or a glass tank that you maybe have lying around probably trumps the option of building a plywood version.

It could be costly from a financial point of view, unless you're just using up materials from a larger plywood tank build. Also, I think a little more consideration would have to go into the building of it, especially if it's for underneath your display tank in an enclosed area. As mentioned, the humidity, in time, would play havoc with your plywood sump unless you coated the tank inside AND maybe outside with your chosen sealant.

As mentioned, there's easier options.

 

[duanes]

What are canisters?
They are tiny, pressurized sumps, that hold tiny amounts of media, are underpowered (compared to my average sump) that need O-rings and such to keep them from leaking, spilling all over, and coming apart at the seems, and that need to be torn apart to do proper maintenance on, so often are ignored until they become nitrate spewing smog machines.
Most of my sumps are/were 50-75 gallon tanks, I found on Craigs list for next to nothing, that hold vast more mechanical and bio media, are user friendly to do maintenance on (again in comparison to a pressurized can) and that, for me I can power with a flow as much as I prefer.

 

[twentyleagues]

Because a tank stands out in the open not trapped under a ceiling and possible walls that trap the rising wet heat. Have you never gone under a tank with a big sump running? Under my 300g I felt like I was in Hawaii and even set up a small fan under it to keep the wood from getting too wet and rot. Pond armor is not cheap, screws are and plywood can be or can be very expensive depending on the quality [marine plywood is def not cheap haha]... Regardless, the time and materials it takes to cure and set up is more expensive than a used and cheap aquarium you can find on craigslist. Not to mention the value of your time. Im all for DIY but I dont build things that arent worth my time. I can find a 75g for $50 on craigslist and even 125g for $50 if you wait long enough. To just strip a old tank and rebuild it would, once again, be more cost inefficient than just patching or resealing a tank you already had. If you are really wanting an excuse to make a plywood sump go for it, you dont need it to be the most efficient option to be able to do it. Id personally also really like to see how it looks and functions long term but all the pros have obviously never used one and I choose to just use the tried and true method

Well we are saying the exact same thing on price. Its too expensive price wise much cheeper options.
I have had my head under a tank with a sump a time or two.....lol
I've seen large plywood tanks with large sumps under them running for many years without the issues you are refering to.
As stated after you went off by others the out side could be coated also. But better yet it could be in his basement for all we know or in a closest behind the tank. I'm not saying it should be done but it certainly can be done with ease. But cost is the real issue at hand. But if I had leftovers of plywood screws and coating of my choice enough to build a sump why wouldnt I? Besides the coating the next most expensive thing in a plywood build is the glass. No glass needed in a sump broski!

 

[Andyroo]

My though is in part to maximize volume thus minimize maintenance- they would not fit them into a cabinet, they are the cabinet.

Can it happen, the answer seems to be "Yes". The primary caveat to said positive seems to be cost. I'm on an island, as are several MFK members. Anything imported is brutally costly. Anything "different" is brutally costly. A cheap HDPE Tupperware is $20($@&%!!) USD, and absolutely not to be trusted without secondary framing($). Tupperware, old aquarium etc. are also somewhat unsightly and need to be behind a cabinet, and then I'm confined by their pre-existing dimensions, angles, holes, bulkheads etc. ...and the cost of said cabinet.

Ply is imported at reduced duties related to hurricane, so not nearly so $eye-watering = good!
Tropical hardwood 2"x2" rips are nearly free for corners or bracing... though you can barely put a screw through them. They're gorgeous, too.
My wife's carpenter/joiner is brilliant, & he owes me.
Sealing will annoy, but let's see.
Yes, the thickness of ply+brace will reduce volume, but we can tailor it into the space & catch some back.
Building to off-the-shelf seals, bulkheads, couplings etc is more than welcome re. cost & convenience long-term.
Yes to casters - just roll it into the yard for cleaning

fishhead0103666 , don't worry, I'll keep you posted - and I'll have more questions, certainly. This is a busy work-season, so this will be a thought-experiment until January, all pending finding a supply of O'rings for my usual HDPE chemical drums. "Dear Santa..."<https://vittlesvault.com/products/outback-80/>
We made 150Gal 2-chamber sumps for a client's pond out of welded 1/8 steel plate (epoxy sealed) - a bit of scratch rust here and there, but otherwise they're tickity-boo 3+yrs later. Note: the imported "good" welding rods & epoxy came out annoyingly costly. There are photos on MFK somewhere...
Pond liner idea sounds great, at least for a sump. If I can get solar by then (thus not hindered by electrify costs) then that'll be the low-hanging fruit. Otherwise I need to pressurize, or the bills to lift water-weight will kill me.

Thanks again,
Andrew

 

[Blakewater]

Well we are saying the exact same thing on price. Its too expensive price wise much cheeper options.
I have had my head under a tank with a sump a time or two.....lol
I've seen large plywood tanks with large sumps under them running for many years without the issues you are refering to.
As stated after you went off by others the out side could be coated also. But better yet it could be in his basement for all we know or in a closest behind the tank. I'm not saying it should be done but it certainly can be done with ease. But cost is the real issue at hand. But if I had leftovers of plywood screws and coating of my choice enough to build a sump why wouldnt I? Besides the coating the next most expensive thing in a plywood build is the glass. No glass needed in a sump broski!

I mean, if you had the leftovers you could always try it. As I said theres nothing stopping you its just normally not the most A1 choice but that doesnt mean its "bad". And you dont need glass but I would definitely want it on at least the front panel, with sumps you want to see whats going on [or at least I do]. When I first set up sumps I usually look around and adjust media and dividers to make it run optimally and in my experience, usually you dont have the room to put your head over it to look in because the tank will be a couple inches above the tank. I feel like you might be feeling like Im calling you idea stupid and I assure you Im not. All Im saying is why more people dont do it. If you do go through with this Ill eagerly be watching to see how it works. Being a carpenter, I always have tons of plywood and screws laying around to use

 

[Andyroo]

Oops, sorry Blakewater - I didn't mean to sound grumpy and I do appreciate all inputs. These conversations sometimes err first-world-centric, which might have made me sound a little frustrated. In my work, nearly every conversation has to be dragged back from Florida... which does frustrate me.