DIY Indoor Koi tank & biofilter plywood 400 gallon

Since I live in colder climate (northern Illinois) and I'd like to continue to feed my koi over the winter so they'll grow a little and I wont have to deal/worry with pond start up problems in the spring (that and my outdoor pond is on the small side) I've built a indoor tank in the basement workroom. This is also a perfect size for a quarantine tank.
The total volume including filters is appx. 420-430 gallons, 2 pumps (rated at 258 g.p.h. each) one for biological filter and one for mechanical filter and aerator.
The tank is made of 3/4" plywood, screwed together, 2"x4" bolted, liner is .020 PVC 14'x14' from Menards. Bio filter is 17 gal. filled with 3M coarse sanding pads for media, air pump supplying oxygen for bacteria. Mechanical filter is a 32 gal. trash can with a plastic shelf located 2/3 up from bottom to hold a bucket the pumps set in, media is cut-up reusable furnace filters from Home Depot.
Currently there are 9 koi, (2) 4"-5", (5) 6"-8" & (2)10-12" the tank is probably maxed out as koi are getting larger, but water parameters are good & constant. The filter does need cleaning about every 5-6 days, this also gives me the recommended (10-15%) weekly water changes as well. I feed the Koi 2-3 times a day.
Since the video was shot I've replaced the garbage can with the same size only a little heavier duty and added a larger bottom drain instead of the side drain as shown in video. This winter probably the first of December (2010) I'll bring them in, I plan on then using the outdoor 55 gallon up flow primary filter (see outdoor pond video) and a 900 gph pump as the koi have gotten quite a bit bigger. I also plan to 'cull' the heard a little, keeping 5-6 koi over winter.
thanks

Category:

Pets & Animals

Tags:

• DIY
• koi
• pond
• small
• wooden
• tank
• indoor
• Quarantine
• winter
• storage
• bio
• filter

[aerohusker]

please read comments below.

[JimFritzMI]

Aerohusker, what dimensions are this tank? How deep did you fill it? It looks as if you used regular BC 3/4" plywood, yes? I am building a grow out tank for my basement, and this is remarkably close to what I was envisioning. The main difference I had planned was running the trusses for the sides vertically.

[aerohusker]

Thanks, the tank is made from 2 sheets of 4’x8’ plywood with a 14’x14’ vinyl liner. Ideally you want to go with a 4’x4’ square for max volume. I went 5.5’x2.5’ due to space limits. The greatest pressure is in the middle of sides, going vertical really doesn’t add much strength as horizontal would. I also added steel cable for insurance.

[elegantkoiponds]

Hi their it looks great but I do have a sugestion for ya add a bigger pump they make external pumps that do 1500 gph and that would be a good flow for the tank. ( smaller pond usally need to be turned over more due to the high fish load they usally have) Also you might wanna add somem ore filtration. But everything looks good and the koi are happy thats all that matters right ?

[aerohusker]

Thanks, but 1500 gph is a little overkill. Depending on the load, it should be ok turning over at least once per hour to hour and a half. With two 258 gph pumps, 32 gallon primary filter and 10 gallon biological filter, with the koi in video it was more then adequate keeping the water in safe parameters. Now this winter (probably the first of December) I’ll bring them in, I plan on then using the outdoor 55 gallon up flow primary filter and a 900 gph pump as the koi have gotten bigger.

[kathshah]

Does 3/4" plywood hold very long for a pond?

[aerohusker]

The main support is from the 2"x4" bolted together. I added steel cable for insurance but it wasn't needed. After 6-7 months the sides are just as straight as when new.

[BigMacBook1300]

Awesome

[fishingman636]

Y would u put a pond right there

[Zeamus634]

Nice setup!

[SimpLeeme88]

aerohusker; that's amazing that you made your own indoor pond!! :-) Question, though. I just bought two new small kois from Petsmart, the generic ones. I have a 30 gallons tank for them two only. What type of filters should I get, in order to keep them live and well?

[bekko247]

hi, very nice video and nice kohakus btw, what dimensions are for this tank?

[metroid158]

did u know kois are edible,my grandpa ate a koi and goldfish and said it tasted like carp

[AllAboutFishNFish]

Wow, thats an amazing set up !!!