Backyard Aquaponics
A place to discuss aquaponics

Hello everyone I am new to this forum. i have a question. Has anyone used CYCO hydro clay brand expanded clay I can get a good price. i am doing a ph control test and noticed that about 50% floats. now i have a small amount ( about a cup) to test with, so i am curious if anyone has used it and am i going to have a problem with it in a flood and drain system. Thanks.

I have not used it. But most clay media has a certain percentage of it that floats until it get waterlogged and sinks. My question to you is Why you chose the clay balls over the cheaper but just as good lava rocks?

Generally the rule of thumb is where it's made, if it's Europe it's great , if China forget it. Why choose Clay? Because it's a joy to work with, I've used clay and natural rocks and if I have the money, I'd always go for the clay.

+1

I am quite restricted for funding my AP set up but with a bad back there was no other choice but clay. Plus I want the kids to be able to plant in it and harvest easily.

Lava rock is also not available in all areas, I had a lot of trouble sourcing bulk amounts and no one knew what I was on about when inquiring about Scoria

Earthbound,

Isn't that dependent on what crops you are planning to grow. As I have read some of the taller crops require more support than the clay can give. As I do agree the clay is lighter, easier on the hands, and slightly more appealing to the eye. But Rock gives better support, is cheaper, and generally lasts longer.

clay balls:

* light weight - GB weighs much less.
* much easier for people with sore hands /arthritis etc to dig into
* can simply push seedlings in with fingers
* get moisture retention - which is positive in a timer F&D system.
* porous surface for bacteria
* "softer" on plant roots

main negative is the cost for the amount needed in GB's.

rocks/scoria etc work fine, particularly in a CF or siphon where wet all time.
but in locations where gets hot the rock surface does heat up.
Most notable difference between rock scoria and clay balls I have used.


so +1 to EB's - "if I have money, Id go for clay" (IMO as well)
But not everyone does and lots of AP have good results with other media.





Most brands of clay balls, including Hydroton, float or have floaters.
Good at blocking up pipes

I get mine from BYAP (in Perth) which EB mentions, and it floats as well.
I ran short when setting up one of my GBs and the whole lot rose and fell until I filled it up.
I have 'used' clay balls that float just as well as the new stuff.

It is most critical that the maximum water level is 5-10cm below the surface (ie. approx length of fingers) - slightly less OK for a F&D but need bit more in a CF so the roots have enough unsaturated media.

The advantage with Clay over rock media is it will hold moisture and you get some wicking/wetting effect where balls just above the water are often quite damp.

p.s. I had some Chinese clay balls (given to me in a gumtree PP purchase) and they were fine.
Probably not as good quality but mixed them in with Hydroton fine.

You are testing them which is the main thing.

yes to the support. Not so good to even hold a supporting stick.

I played with Hydroton with rock scoria on top to get better support and in my Dutch Buckets I used 50-50.
(hence comment above about the rock heating up). Also looked at other way around with rock in saturated area and Clay on top.


"generally lasts longer" - yep, pretty hard to wear down.

Clay balls do seem to crack and chip over time.
But it will still go for years.
All OK if you have trellis or a frame.

Thanks for the replies, I have a system with expanded shale, the one i am building now is for a culinary arts school so I need to make it as user friendly as possible and the place where I picked up my shale is no longer open (it was great 1000 lbs for 35 dollars) i tried to use the plant it brand but i had severe ph issues. So in my search for shale i came across this brand and was wondering if anyone had used it. thanks

No... These are more of the points people have made up over the years, yet appear to have become 'truths' repeated over and over again, yet not necessarily based on fact. There re lots of these in AP, a fluctuating tank level stresses fish, turning pumps off and on ruins them, you must have solids removals, etc, etc..

Expanded clay will last indefinitely, I've had clay in a system for going on 10 years without issue, will it start breaking down over the next 10 years, or the next 20 years? Perhaps, will any off the other components of the system last this long anyway? What ever happens it's not really a reason to choose rock over clay or vice versa.

Support? I have never seen this become an issue, has anyone actually had a problem with tall plant support in clay beds? Might need a new thread on this. I know I've seen people raise this in the past, that rock media provides the support you need for tall plants but is that actually based on any empirical evidence? Did someone have a brand new system and their new plants blew over once in a strong wind perhaps? I've grown many tall plants in dozens of AP systems using clay and never had a problem.

I think I'll start a new thread on this sort of stuff...

Earthbound,

Thanks. As we are all a product of what we are taught. I look forward to the info on your new thread.

Thats how we all learn aint it, from others and our own experiences.. I'll be interested to see what others experiences are..

viewtopic.php?f=1&t=24039