It probably depends on how well you're getting media drainage. If the timer system worked the pump only had to run a small fraction of the day, and coco coir drains slowly, so you'd have to be careful not to keep it too waterlogged with the constant siphon cycle going on. It doesn't sound to me like the frequent siphon draining would help???

If the medium were larger pieces of stuff like rocks and hydroton, the retention would be less and the siphoning action would probably aid by aerating, pulling air through the big spaces, but I don't see that benefit with slow draining coco coir.

If you wanted a 50/50 mix (or whatever the right proportions turned out to work best) of perlite and coir, that might complement better the continuous siphoning ebb and flow with superior aeration.

If your water source were from a fish tank though, the continuous system would probably provide more ammonium oxidation for the fishes' benefit, but balancing fish requirements with variable seedlings might not be something fun to deal with.

This post was edited by PupillaCharites on Tue, Mar 18, 14 at 2:19

I bought a bag of cyco coco pearl. Man what a waste of money. I contacted the tobacco supply place about an hour from me. They have the stuff made for this for 9.00 a bag as opposed to almost 30.00 for the pearl and a 5 lb bag of vermiculite. As usual, it says hydro so it is worth almost 3x as much!

I am going to pick up some trays too, enough for about 5000 starts.