I know most people say to use the clay pellets for a ebb-n-flow table, i had to get this set up right away and did not have access to the clay pellets, so i opted for river rock to put my rock wool cubes in so far they seem to be doing fine, but are there any downfalls to using the river rock, i am not using the pea sized gravel but the next size up,so was this a bad idea or will it work fine? please let me know. i do know it is a lot heavier but it seems to retain the moister well,any input is greatly appreciated. my table is a 3'x4' under a 1000 hid.
sure it will work. Clay pellets retain some water, river rock will not. But since you're using rockwool for water retention, you will be alright.
One more quick question, my ebb-n-flow is a 3'x4' i have five misty's they are about 2 1/2 weeks old and about 5-6 inches tall on there 5th node, do i let the rock wool dry out a little before i flood the table"not dry but kinda moist" or now that they have a decent root system just flood them 2-3 times a day?
On the next grow get hold of clay. You are going to work non-stop to keep this grow going. You'll need to flood the table more often because the solid rocks aren't going to hold moisture like clay would. You can't rely on the rockwool to supply the water needed down the road. The roots are going to spread through out the entire table pulling water/food where they can. In the past when I've done ebb and flow, I would normally flood 3 times during a 12-hour light period. Never in the twelve hours of dark. I would think you would need to flood 4 or 5 times to keep everything damp. I quit growing hydro opting for soil for less work. I was always working the ebb and flow tweaking and monitoring. Soil ended that carp. I'm much happier now for that. Each to their own though. The root system and the canopy have an inverse relationship. By that I mean, the bigger the canopy grows the bigger the root system will need to be to support it. The root system isn't what i would call decent at 2.5 weeks old. They still need 3 or three more weeks to get going. The stronger your root system the better you will be once you start thinking about flowering. I would give it a few more weeks and let the roots develop to the point your plant are 12 to 15 inches tall. Then you can say the root system is decent. Also be gentle with the food right now. You can burn those little babies in the blink of an eye. Above all be very patient as you grow. It will pay off in the long run.