Backyard Aquaponics
A place to discuss aquaponics

guys are there any difference between hydroton and broken clay pots? aside from how it look (round and sharp) because hydroton is expensive here and scarce plus its smaller than what you have there.

Thanks

Jamesto, hydroton are furnace fired clay balls, so in a sense not a lot of difference.... other than the firing process used to manufacture hydroton results in lots of air pockets being formed within the clay balls.... hence their light weight...

Broken clay pots have been baked and I would expect probably don't incorporate as many air pockets....

Main differences then ....

clay pots will probably be heavier for the same volume, maybe not by much - haven't compared....

one of hydroton's main advantages as a product is that although appearing smooth, they actually have a surface punctuated by millions of little air bubbles and as a result would have I suspect a considerably greater surface area available for bacteria growth.

for similar reasons I suspect that the hydroton would probably drain better than the clay pot fragments.... only a supposition, but I'm wondering how porus or otherwise the clay pot fragments might be....
i.e how much water they might retain, and whether you'd need to adjust the interval between flood cycles so that they didn't remain water logged??

Hydroton is a lot smoother and easier to plant/work with than broken clay pots.... unless you have a way of breaking them down into fairly small pieces, even then there will probably be sharp edges.

On the other hand if as you say hydroton is expensive and you have an abundant supply of clay pots, then sure why not use them

I know members here have used them in/as bio-filters within their systems...

Are you thinking of using them as a bio-filter in say a drum or were you thinking of using them as the growbed medium?

as a growbed medium however I have another option which is lava rocks (red one and crushed) however what I found here were fine around 2- 3 mm. thank you...

Just bear in mind, at that size , whether or not they could make their way into your pump... wouldn't be too good for the pump I suspect.

the other thought I have Jamesto is at that size whether or not they might kind of compact down and "co-agulate" ..... in other words, would there be sufficient spaces between the particles for air (oxygen) to be sucked into with the drain cycle.

Most growbed mediums are usually around 8mm - 20mm.

Have you thought of using coco-peat, coco-coir.... which is just shreded cocnut husks/fibres.

Over here it's available in compressed bales.... surely there must be plenty of it around your way?

Otherwise lava rock (scoria or pumice) would be fine.... just might have to wash it first. There are a few others that have used it quite successfully.

Doesn't weigh as much as gravel, biut would certainly be heavier than other options, so you'd have to build your growbeds/stands accordingly

hmmm we have a lot of coco peat here, its cheap and sterilized am using flood and drain (continously) however my concern is that the cocopeat is like mud when wet it might go to the fish tanks.

has any one been successfull with their systems using cocopeat?

I think murray has

yup I saw it already I guess i would just need to look for bigger lava rocks heheh

Murray has used it and found it to be ok with the following provisos....

It does initially discolour the water unless it's thouroughly rinsed several times before use.

You should probably rinse it anyway as it has often been harvested and rinsed in sea water and can have a high salt content.

As it retains water so well you need to be aware of the fact and significantly modify your cycle times.... I'm not sure that running continous flow (even with auto-siphons) would allow sufficent drainage....

Gary has had some great results using it as a medium in pots... but he has been hand watering them.

I've thought about this media and possible problems for a while Jamesto and I think it could be successfully employed if you can get and use coco chips, rather than the (compressed) fibres..... ie chips like mulch chips which would allow better drainage and air spaces...

do a search on "coco-peat", make sure you select "posts" rather than "threads".... you'll find lots of references.

Perhaps it's real use may be in combination with something like hydroton, vermiculite or even mixed with scoria/pumice ... just to open it up and allow some more air into it

Surely pumice would be an option over your way as well.

thanks RupertofOZ i'll give it a shot

I would say broken clay pots would have more pores than gravel, but not as many as hydroton. If that's what you have, then use it. Break them to a size you like.

Hydrotron is fired at a similar temperature to most good ceramic pots. Hydrotron has organic matter mixed in with it so when it is fired the small bits of organic matter burns away leaving lots of small holes and pores.

I made some stuff a few years ago and mixed in coffee grounds and saw dust.. Turned out like honeycomb almost. They where fired at 11-1200 degrees C.

good one tim! i like home made stuff!

Except try rolling out clay balls by hand..... I didn't make many....

Thats why I was looking into making them on a large scale... I need a large tumbler and water sprayer to do it... I wanted to form them over bean bag beans so they would be hollow.