grow rocks and porosity question...
 

When we talk about the ability of a medium to hold oxygen aren't we talking about the air gaps between the particles that makes up the medium. If this is the case then it seems to me that plain gravel would be just as efficient as clay gro-rocks.

Or are you guys referring to the porosity of the medium?
I'm using pea gravel and everything seems to be fine, although I was hoping for a faster growth rate vs. soil. It's only been 4
weeks now and I started almost everything form seed so maybe I'm over reacting.

In your experience is there a point in a plants growth cycle when it really kicks in and starts to take off. If so when?

Maybe I need to try gro-rocks and do some comparison studies vs. gravel.

Grow rocks work so well because they are pours and gravel is not.

Hello guys,
i'm from good old germany, so be so kind and ignore my bad grammar :-)

Can you tell me something about seeding on gravel ?
I try at this moment 1-2mm, 2-5mm and 3-5mm split.
Split is very dry after 1 till 2 hours.

Have you got some pictures ?
When i arrive at home, i'll post up some pictures of my "sand".

Edit:
Here is my actually testsystem
http://cossy-network.de/bilder/syste...8_21062009.jpg

Kind regards
Tiggar