Quote Originally Posted by ICEToker
the idea of using rocks is to support the plant roots, but not to absorb water...
Hygroton is a brand name...they work very well...I use em...cleaning is a bitch-a-roony, but do-able...{baking in oven for a little while works wonders}...
Hygroton is very smooth and lava rock is generally rough and porous...I've heard it said that the rough rock has more to grab onto...I've never had a problem with Hygroton...I also use rockwool cubes to start seeds and clones, I love it also...I dont grow in rockwool only because it holds water too long, but it does fine for clones and seeds...
Now just a quick comment on this posting. Hydroton is expended clay pellets it is the most porous surface currently available for hydro growing. I can't use it because it floats when I flood my system instead I use regular natural aquarium gravel. I don't use rockwool anymore as it raises the PH at the root zone and in my experience has slowed growth. I think sometimes we get caught up in media - media just holds the roots - the difference is the frequency of watering needed to keep the plants growing at the maximum rate, and how easy it is to remove the excess nute build up that reusables have. Aquarium gravel holds water for a short period of time 4-6 hours depending on the size of the plants. Because of this short period less water has a chance to evaporate on it's surface and so less excess nutes are left behind to spoil future crops. Very practical only requires rinsing between crops. Both hydroton and lava rock will have higher risidual nute build up because of the relative porosity of both. Baking it will only make this problem worse over time. It is however still an excellent media for a while, and in fact you may never have a problem with it.

Herbus