Plywood tank questions

[Burton]

I have been scowering the net looking for a good written out plan on the wood needed to build a 300 - 600 gallon tank and have been unsuccessful.

 

I have seen koi ponds with no details to the wood thickness and necessary spacing of 2x6 ribs used, and I have seen aquarium builders using 3/4" plywood only with epoxy and glass.

 

Does anyone have any information so I can start to plan out the cost for the wood / fasteners / misc ?

 

Also in regards to EPDM pond liner, aka fish safe pond liner, I just read over at friendly aquaponics NOT to use this in your system ... what are the other options outside aquarium safe epoxy / fiberglass? Is there another "safe" pond liner I can use or am I missing some information?

 

 

Side note: Right now I am comparing costs of different tanks and beds as well as making a 1:1 scale of each option on my photoshop layout of my condo to see where the items will fit best. It seems IBC and making my own tank would cost about the same or close enough where making my own tank / beds would benefit me more given the space I have.

 

Thanks for your help

[Burton]

@Rick

just curious why flout a GB over using bell siphon?

Also to avoid the water level being an issue in one of your ideas why not just have a dual tank setup where the water overflows into the other tank out one side of the FT. And the tank it flows into has the FLOUT connected to the Indexer etc.

 

@TC

yeah humidity is going to raise considerably, thankfully I already have a spot in my house I can easily install one and drain to an overflow next to my HVAC. I use to have the pondmaster 960 in a custom made water cooler for a computer I once built, it isn't too bad but it is a bit noisy.

 

I have been beating my head against a wall these last couple of days trying to figure out a way to get most of the GB's on the second floor without moving the tank up there as it will probably weigh too much even though the structure is only 4 years old. -_-

 

[Rick Op]

Burton Rosenberger said:

@Rick

just curious why flout a GB over using bell siphon?

Also to avoid the water level being an issue in one of your ideas why not just have a dual tank setup where the water overflows into the other tank out one side of the FT. And the tank it flows into has the FLOUT connected to the Indexer etc.

 

Aha, the infection has taken hold. That's the config I call the "Sidecar." If and when I build an above-ground ferrocement FishTank in my backyard, it will indeed incorporate a side-tank, FLOUTed.

Why the FLOUT? I like both loop and bell siphons just fine, but I believe the FLOUT to be more elegant, more fun to watch, and can be scaled up to huge pipe diameters. It can incorporate a magnet to operate a switch as we discussed, thereby automating other parts of my system (even if only to turn on an LED in a faux-mini-lighthouse to let me know the system's running). The main force driving the FLOUT, buoyancy, is formidable. There is no water flow until there is a LOT of water flow.
Drawbacks are the room it takes, a few inches of water left in the chamber, and you end up in a distinct minority...
See also this.

[TCLynx]

Flouts require quite a bit of space to operate which is the only real drawback I see to them.  They have the elegance of being able to operate over a really wide range of flow rates, the top of that range being the amount of water that can gravity flow through the pipe and the low end of the range basically being something above a drip.  Siphons are much more limited in the flow range where they will function but they don't take up much space.

[Larry Reinhardt]

I just read this and even though it may be to late here is how I build my tanks.

 

http://guppydesigner.com/index.php/guest-bloggers/141-larry-reinhar...

 

I'm now using it as a tilapia spawning thank, I moved the sponges up to the tank partition on the right so fry get sucked into  that and out of the big chamber.

Larry

[TCLynx]

Good Blog there Larry about building the plywood tanks.  Do you have any additional tips about the glues and the epoxy coatings for the plywood as well as how you do the glass fronts?

[Larry Reinhardt]

The walls are glued and screwed to the bottom using good old Elmers Wood Glue, I use epoxy paint from Aquatic Eco Systems.  I use the clear as I like the look of it, it does come in colors and when I used to build tanks for customers I stained the outside to match their furniture. As long as the tank isn't more than 20" deep double strength window glass will work and just silicone it to the wood. I use wood for everything my FT is 20' x 5' x 3.5' using treated 2" x 12" x 10' mostly, I put some pictures over here http://www.backyardaquaponics.com/forum/viewtopic.php?f=45&t=10208

[Rick Stillwagon]

I have built a few wood tanks and it is well advised to overbuild.  Water places a lot of stress and pressure on the structure. I know you can get IBC containers for $75 to $100 around here. A well built wood tank will cost more and unless well sealed or preserved in some fashion will have a relatively short life in comparison. Cedar lumber and treated plywood with a liner are your best bet for a wood tank.  

[TCLynx]

After my experiences with lumber and liner I will no longer use liner against lumber anymore.  The moisture from condensation between the liner and the wood invites rot and insects (even with treated wood) and here in the outdoors in Florida with termites I won't do that again.  Liner is great but not against wood in my book at least in FL.

 

Now I'd be interested in hearing about the long term longevity of the treated wood sealed with the epoxy outdoors here in FL.

[Rick Stillwagon]

I gave up on wood tanks long ago. Too much stress on the structure. Wood and water just do not mix well. I have built several wood hot tubs and they do alright if you care and maintain them. The lumber for wood tubs/tanks (cedar, cypress, teak, purple heart,) is very expensive and is more of a luxury/novelty. Treated lumber is toxic as well. Epoxy will seal, but should be reinforced with fiberglass to prevent cracking. The investment in a good plastic tank is money well spent. Concrete is good too just make sure it is well reinforced and proerly cured, filled and drained to leech residual minerals from the cement. 

[Harold Sukhbir]

Hi Burton,

Try this http://friendlyaquaponics.com/docs/2010FREEPlywoodTankManual.pdf

[Larry Reinhardt]

I use wood for two reason 1) It allows me to make custom shaped tanks and 2) Its cheaper. I have used wood since the 1970's and not had any bad happenings. If I make plywood tanks I used the wood as described by 'Friendlies' above document and if I used treated lumber I'd line it with EPDM after I let the lumber shrink and seal the cracks with spray foam. I know that the tanks and raceways will last at least 10 years without problems or termites because that's how I built my first Koi farm. When I sold the farm everything was in good condition and nothing needed replaced. Try buying a tank shaped like a 'T" 30" deep with planters under the arms of the 'T" with built in lights or a raceway 40' long with a 1/8" drop every 3 feet in rubber or a plastic poly like material. I use IBC and Rubbermaid tubs where I could however it always seemed what I wanted to do was custom stuff. Looking on 'Youtube' you will see several large Aquaponic and fish Hatcherie's commercial installations using lumber for the walls of their raceway tanks. Rick is right you have to oversize the supports on tanks more than 18" or so deep. You can use 2" x 4" if they are spaced correctly and anchored top and bottom to a frame. In the tank I just built 20' x 5' x 3.5' I also used a 6' alltread rod across the top of the 4" x 4" post which support the wall 2" x 12" lumber. In conclusion I will continue to use what I found successful over 60 years of fish raising and organic gardening in Florida - to each is own and good luck to all.