Backyard Aquaponics
A place to discuss aquaponics

hi friends, i live in tennessee and have a 24foot x 48 inch pool that is no longer used. i am thinking about using it as a fish tank, with a 100 foot x 8 foot grow bed about 2 feet deep, i would circulate the water from the bottom of the pool through the grow beds and back to the pool using my pool pump. could this work? comments and ideas would be welcome

Welcome randellww!


So you reckon you'll have 10,000 - 12,000 gals (38,000 L - 45,000 L) of Fish Tank water?

Are considering DWC "grow beds", or media-based "grow beds"? Or both?

There are some frequenters of this forum that have 20,000 gallon tanks (or pools) that have had great success. Heck, as I recall PLJ's big concrete tank is 90,000 L (almost 24,000 gals.)

PLJ's Big Concrete Tank System
I'm sure you could make it work one way or another.

--
Sam

pool pumps use a lot of electricity and the pumps & filters are not really suited to dirty water.
you may have to look at a more efficient ways of pumping, aeration and circulating water.

as for the pool itself - should not be any real issues. 4' is a good depth.
24 foot presume is diameter - 24 foot = 8 metres, big pool. Most AqC tanks would be 3-5m.
What is the pool material ?

AP 'rules' like turning the volume over per hour etc are impractical at these levels and keeping the pool bottom clear of debris/crap is not so easy (aquaculture often use sloping bottom tanks). Best option is to run a fairly low stocking rate

Filtering will be main issue because it is unlikely you can have enough grow beds and it would mean a lot of media in any event. You cant just have a DWC without other forms of filtering. So you are probably looking at drums for filters or something else (eg. mini-marsh filtering). Also if out in sun you will get algal issues so will need to plan for that and you may have to deal with quite a bit of water loss in hot weather. Quality of top up water becomes an issue - may need a tank.

PJ's system as recommended above is worth looking at but keep in mind his is deep so it stays very cool.
There are also other pool conversions on the forum.

The alternative (but would depend on pool material) is to develop a living pool which will provide the benefit of natural 'within pond' processes. Not many covered here but they are discussed quite widely on the web.
The living pool got mentioned around here a short while ago here viewtopic.php?t=27321.

Not sure how you intend to do your 100ft (30m) bed ? Unless it is a classic commercial sized DWC you may have to use compartments to deal with nutrient distribution and through flow. Is your site sloping ?

Another thing you'll need to research is Bio-Ponds, I have one for general purpose water saving and some other uses.
If your pond has a liner you could pull it up and create a conical bottom with packing sand as well as some ledges for other plants to grow then relay it, all the while reducing the water quantity to a more manageable volume. Grow beds could be fitted around the outer edges so they drain back into the pond.
See pic GBs on left, right and out to a couple of feet short of the platform.

Pete.