Backyard Aquaponics
A place to discuss aquaponics

Hello all, just joined after reading heaps of info on aquaponics. I'm loving this site! Anyway, I am looking at starting a basic system and was wondering if anyone could give me a few pointers on setting it up. I have a 500lt tank, an old sea bouy (spelling?) that I'm thinking of halving lengthways and cleaning, which will end up just under 100lts each and an old bath tub, which from what I can gather, will be about 200lt. I also have a el-cheapo $50 1500lph pump.

Was thinking of using the bouy halves first and then adding the old bath tub later, or using the bath tub as a wormfarm to breed worms for fish food. I really like the sound of the flood and drain systems, but am not sure on which would be better, flood and drain or constant flow. Also, was wondering how to aerate the system with just the one pump. Would the drain back into the tank be sufficient to aerate or do I need a better system? Maybe an aquarium air pump? I would ultimately like to have about 10-15 eating fish in there (not sure if possible or which breed). Also not sure where to get fingerlings from near my area (50kms west of Melb).

Any help is much appreciated. I can see this aquaponics bug becoming a real problem for me, already thinking of bigger and better! One step at a time, one step at a time!

Quachy

Only advice I'm qualified to suggest is POST PICTURES!

500L FT is a good min amount to start with IMHO, I started my first system with half blue barrels for the FT (100L) water temp was to unstable.
Some say you can feed worms only up to 40% of diet, not 100% sure why that is.
Flood and drain is better for the nitrobacteria (others will explain and spell this correctly)

welcome and enjoy

Yes flood and drain does seem to be a good way to go unless you want to get really complex.

I'm tempted to tell you to start off using the bath as a grow bed. (you can always make a worm bin out of plywood)

There are a couple of ways to make flood and drain happen. One is using a timer so the pump fills the bed/s faster than they can drain and then the bed slowly drains while the pump is off, this method might require you to have additional aeration devices. the other way is the let the pump run all the time and achieve the flood and drain with an autosyphon or other auto draining device (like a FLOUT.) This way you can divert some of the pump flow back to the fish tank for some constant splashing/aeration. I would probably suggest you research auto syphons, loop syphons, and bell syphons. Might also be spelled siphon.

Then you will want to do a search on CHIFT PIST to help you decide how to lay out your system.

How much fish can you support will be more related to how much grow bed media you are flooding and draining than how much fish tank you have. For every 100 liters of grow bed you can support perhaps as much as 3 kg of fish. If you were to have 1000 l of grow bed for your 500 l fish tank, you would need to add a sump tank to the system to allow enough water to flood and drain all your grow beds while keeping enough water in your fish tank for the fish. That example is what people call a 2:1 ratio growbed to fish tank. The 2:1 version would need another large tank as a sump tank but could possibly support 30 kg of fish at peak. Perhaps 15-60 fish depending on how big you want them before eating.

Most people start with something more like a 1:1 ratio or equal growbed and fish tank in which you might manage to function without a sump tank though the fish tank water levels will fluctuate a bit. A 1:1 ratio system with a 500 l fish tank could perhaps support as much as 15 kg of fish. That could be anywhere from 7-30 fish depending on what size you want to eat them at.

I hope this helps some and I know I gave you homework to go look up some stuff but I do believe there is something to be gained by reading lots here before killing any fish.