Backyard Aquaponics
A place to discuss aquaponics

perhaps you could re-edit you previous post and remove the url.
as you may have noticed no others are mentioned, except for the portal page.
No reference/promotion needs to be made to other sites here.

No problem Aquatom....

All systems design and other questions welcomed Aquatom.

Hi Aquatom, if you are wanting a budget system, how are your scrounging skills? Many of us have sourced used bath tubs for grow beds, cheap and sturdy.
Welcome to the forum

Welcome to the forum.

No worries with bouncing ideas off us here

Have a look through the members systems (there are a selection if diff. sizes "stickied" at the start) for some alternate ideas.

somebody mentioned expanded clay as the lightest most manageable media for my system, where can i get this? and what will my clay to water ration in my grow beds be like?

Basically the same as gravel aquatom, about 60/40 ... I think....

You can get hydroton at most hydroponics shops, Bunnings and a lot of nurseries.....

I would probably start with a small system first aquatom, work out the kinks and learn how to manage a small system first. that's what I did, I have a fish tank with a small growbed elevated above it using flood&drain with a small aquarium water pump on a timer, the pump acts as a syphon during the drain time.

Cost me about $100 to set up ( already had some gear ) and is going great guns. Am about ready to plunge into a bigger system, will probably usewith bathtubs and a IBC if I can find a suitable one. I like the idea of using recycled items in AP, kind of goes with the spirit of the whole thing.

Welcome Aquatom. I get my hydroton from the Nerang Hydroponic Centre. If you buy quite a lot, the price drops.

Up here $30 is the best you are likely to get it for largish purchases.

i was wondering what the min depth of water in a tank can be before the fish start to die and have problems

Depends on the size of the fish. I wouldn't design a system to have any less than 60cm of water on the flood cycle, though my original small system didn't even have that on the drain cycle.

I was thinking of go for something that had 35cm on the the drain and 25cm on the flood as a realy small test system. But do you think that would be small of i wanted to grow sliver prerch to 500g?

I'd start out small, i did and i've had hardly any issues.
buy 2x 220L nylex tubs from a hardware store (i got mine for $35 each), get some old bricks and sit the grow bed on planks over the fish tank, just offset a little for easy access.
get a $30 pond pump - mines 950L/hr and work great.
grab some scoria from a landscaping place, should cost bugger all for 220L.
some piping etc, another $50 at the most.
and buy goldies to start with - tough and cheap.

done right you should get a working system and change out of $200.

Short answer is yes (too small for 500g silvers). Get your ruler out and look at what 25cm is. Also remember that you will lose water through evaporation and transpiration, so between top-ups it will be even more shallow.

Timmy - you don't have 500gram fish so with no offence intended, your setup is not really able to be used as an example of what tom is talking about.

Yep veg, hence the goldies advice.
Now that i've seen the work involved first hand I wouldn't want to try tackle a system that's going to grow large fish right away.
get a system running first, even if it doesn't have edible fish in it it'll still produce lots of veggies and give you plenty of sludge to seed a larger system, and give you lots of design improvment ideas.