i am no doubt a caveman when it comes to figuring this stuff out,but this is my general idea. I could buy one of those stock tanks at tractor supply and put it in my garage to try to keep some tilapia alive this winter. I have a well, so i wonder if i could figure out some way to do a complete water exchange ever so often (how often i don't know).Maybe just a simple electric water pump to pump it out. Would this strategy eliminate the need for any filtration system, since that part seems relatively complicated? I guess i could buy a big aquarium water heater to keep the water warm enough. What's wrong with this idea? My caveman mind has a hard time comprehending concepts like bio-balls and biological filtering, but if that's what i need to do i,where would i get that stuff, and how would i marry it to the tub? Maybe a 5 gall. bucket attached to the top edge of the tub,filled with the bio stuff.Just pump it up to the 5 gall bucket,let it trickle tru,then route it back to the tub? I have killed every aquarium fish i ever owned So this could be a challenge

Here's a good start, http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Number=95836&fpart=1

Meadowlark used an old hot tub with success, search for his thread on the subject. Theo Gallus has done some work with cold water species as well. Maybe search RAS (recirculating aquaculture system)

It'll likely stink up your garage and you'll have a lot of moisture build up = rusty tools but you may be better at it than I.

Howard:

See Bruce Condello's Cecil Envy thread for the story of the original Po' Boy RAS: A trough, a hose bib, a man, and a dream.

PBRs are pretty easy to run. Smells and humidity problems are minimal with a cover and a dehumidifier sitting next to it. Water temps are naturally easier to keep up if the tank is in a warmer environment. Mine is in the basement and stays at 73 deg with a 300W heater full time, 600W while water is being added.

Get the PB mag article that Theo authored (Jan 07) IIRC.

thanks fella's.some real good info in those links..If i get it off the gound, I'll post some pic's..

Well i got it set up.Looks basically like the one Bruce made.
I put w 300 w. heater in the 150 gal. rubbermaid tub, and it has almost no impact on the water temp.I guess, due to the constant inflow of 68 deg. well water. At 68 degrees, is that warm enough for them to thrive? I don't think it will get much lower than that,since they are in an pretty well insulated garage.

They should do fine at that temp. and eat/pollute the water a little less too. If your looking for max growth you'll need to kick it up into the 80s but they would likely outgrow your tank by Spring. If your looking to just hold them until Spring, the cooler temp and meager rations will make it easier. My pond is in the mid 60s and the tilapia are still active but they are slightly more cold tollerant species than yours.

how many 4-5" tilapia do you think my tank can support over the winter?

I was caught a little off guard by how quick my big tilapia became inactive.My pond water temp went from low 80's to 60 deg. in about 3 wks! So, i didn't catch as many big ones as i wanted, for eating purposes. Next year i'll havest them in late summer,when it will be a lot easier.

Howard, I overwintered 26 RES ranging roughly from 4"-8" at the start of the season in a 100 gallon tank last year. I am sure you could do 100 4"-5" Tilapia in 300 gallons with a similar maintenance regimen. Increasing the fish load would mean more frequent/vigorous cleaning and water changing.

I had 750 in a 625 gallon tank ranging in size from 2" to 8" (mostly 2" to 4"). I started developing serious water quality issues after 2 months. I've read that with a proper set up you can raise 1 lb. of tilapia per 1.5 gallons but about 1/4 that rate would be max for a non-pro.