Backyard Aquaponics
A place to discuss aquaponics

After my last grow bed medium caused a very high pH which killed all my plants, I'm trying again. This time I'm using Seramis expanded clay granulate, which is specially made for plants. I'm not sure if it will cause problems for the fish, but we'll see about that.

The Seramis granulate is very light weight and very porous. If you put a big pile of the stuff into a shallow dish with water, the capillary action will suck the water right up. This means you can have a constant drain system and all of the grow bed medium will still be wet all the time. No messing around with siphons or timers.

I've used a plastic tray that I had laying around, it is one of those trays that you put under your washing machine to contain the water in case your machine starts leaking. A drain hole covered with a drain sieve sits directly above the fish tank.

One other thing I really like about the clay granulate is its color, the orange color combined with green plants looks very nice.

Hmmm, that would work really well mixed in with normal gravel, it may be too wet constantly for the plants. Your definitely right about the colour

I put a basil cutting into the grow bed and it started to grow roots! It's amazing how easy cloning is with an aquaponics system. I just cut a piece of the plant and stuck it right into the grow bed. Look at the roots after just two weeks

Try putting your system on a timer - the cycle of dry and wet seems to promote good plant growth in a lot of plants - if wet all the time the plants just dont 'perform' as well as those which get a dry cycle...
I would not mind getting some of that stuff myself! look stunning!

For the plants, the constant trickle though the bottom of a grow bed seems to work ok. To get more bacteria growth for your bio-filter for your fish, flood and drain does seem to work a bit better as it lets the bacteria work on more of the water to do the nitrogen cycle conversions for you.

However, I think I would leave that particular plant tray as it is and use it specially for rooting cuttings and growing stuff like lettuce etc. Your next bed (since there always has to be more!) can be flood and drain to expand your bio-filter capacity as your fish grow.

I believe the expanded clay is a wonderful media for Aquaponics. I've never used it myself as I'm cheap and I can get quartz river rock in the appropriate size for $52 US a ton. The expanded clay around here I believe costs about that per 50 lb bag.

Anyway, I love the rood growth picture, isn't it great! If you were to use a timer to make flood and drain on your next bed work, I expect that tray would be find with a bit of drying time so it could all be on the same pump/timer probably.

Doing well. don't give up!

There should be a few more coming real soon. The beds are all ready and waiting to be filled.

The expanded clay is very expensive, but it has a few advantages. I will probably get a cubic meter bag of it to fill some more beds and fill some others with gravel (after testing it...)