Backyard Aquaponics
A place to discuss aquaponics

HI
I am new to aquaponics and I am attempting to set up a two grow bed system , Using the top from a IBC and a bath located above the IbC I am concerned that if i flood both beds at the same time the water level in the fish tank will be reduced too much . (Approx750 litres )
I beleive you can purchase a Indexing valve] that would allow me to use a timer and flood each bed separately .
Has anyone had any experience with these ? and if so what brand pump and size would you recommend . The max head height would be 1 metre and the bed sizes approx 250- 350 litres in area in each .
Any advice or help would be greatly appreciated
Stuboy

PM RupertofOZ - he knows all about the indexing valves.

Hi Stuboy, and welcome to the forum.... I'd recommend a pump that's capable of 3000L/H at 1 metre head...

But it might be worth going a bit bigger... depending how many beds you have, or intend having....

Drop me an email via the website in my signature... and I'll talk it thorugh with you...

Or you could run one bed as constant flood and the other with an autosiphon and this would not drop your fish tank much at all. You could also run both beds constant flood and the fish tank would not change at all.
If you look at the BYAP trials thread, the constant flood bed is doing as well as the others

By the time you add the gravel to the beds the volume of water will be reduced to roughly 40%. 700l in gravel requires about 280l of water, even if both fill at the same time (flood and drain, or worst case with siphons) the fish tank volume wont drop by any more than that.

Indeed... with such a small system... the aquaponics valve probably isn't warranted...

If you're really concerned about the draw down of the tank... by filling the beds and waiting for the siphons to commence...

Just use a timer and overflow standpipe... with a couple of holes in the bottom of the standpipe... which will begin draining water back to the tank immediately... and virtually act as a "constant flood" for the timed interval once the bed is full and overflowing through the standpipe... then slowly draining until empty...

Simple as... and reliable....

And yes... timers can fail.... but rarely do.... and if they do, are easily replaced... and the beds will always drain...