Preping My Ebb & Flow Table Using Big Rw Cubes

**mogie** · 03-21-2007, 01:13 PM

Yes, those small square planters are very restrictive as far as giving adequate room for rootmass. They are really only productive if you are growing from small clones, otherwise they tend to stunt growth and thus reduce potential yield.

Modifying them to have more holes around the sides near the bottom is a must, it will encourage a nice healthy root mat in the tray around the planters.

Building a cover plate to suspend the square planters over the tray will allow the roots to freely flow out of the planters without any possible damage caused by the weight of the planters sitting on the root-mat and blocking the holes. (similar to picture below)

Better yet, use orchid pots or net pots, suspended over the tray by a cover plate with holes cut to place the pots thru.

The suspended planter or *orchid pot method provides the maximum for root mat development. The optimum root mat develops when a modified orchid pot co net pot is used.

Modified (left) and standard (right) Orchid pot co netpots
*Orchid pots are heavy duty net pots made by the Orchid pot company, they are better than ordinary net pots because they have a flange molded into the top of the pot, allowing for the net pot to be suspended in a hole without the risk of the combined plant/pot/rocks weight causing it to fall thru the hole. Orchid pots are available from grow stores and they usually sell for about $1.50 each (10 for $15.00), good cheap and easy to use.

The modified net pot allows for superior root growth and prevents common root damage which can happen when the roots hang down over the sharp edges of the plastic net pot openings.

Another option is to simply fill the entire tray with grow rocks and forget about using any pots or planters, this will give an adequate root growth space. *Almost as good as the suspended orchid pot method.

**mogie** · 03-21-2007, 01:22 PM

Rockwool Prep:

In this application, running tight spaced cubes with the intention of doing a spike type, mostly single cola grow, 218 cubes are placed into the table. Thats a full table, less 2 for the fill/drain holes. The tray is first flooded to the top of the cubes, with water at PH 4.7 and allowed to stand for 12 hours. This helps keep them from drifting up in PH. They are then flooded with straight tap water to rid of any debris that may have come in the manufacturing or handling of them. Next they are flooded with PH 5.7 water, at this time the cubes should be at PH 6 and ready to accept clones. This is also a great time to check that your table is level.

Each table is a standard 4'x 8' ebb & flow with 2 x 1000wt HPS air cooled lights. Air stones are added to the table and large four inch rockwool cubes are the medium. The cubes are covered with mylar and "X" cuts into the holes that accept the 1" rockwool cubes. This is done to help keep the roots dark, keep the algae growth down and to reflect a light back up to the plants when they are small. I use a very small submersible pump for pumping the water to the table, a couple of shut off valves are also helpful to control the flow and also keep the water in the table for PH adjusting the cubes. A digital timer is used here so that the flood time can be adjusted to the minute.

Above dual picture, shows prepared table with pre-vegged six inch clones inserted and ready to go. Tables are flooded one hour after lights on and again every two hours after that for a total of six feedings during lights on, nothing is used at night. Flood height is adjusted to roughly three fourths of the cube height, and takes just over six minutes to fill, pump runs for eight minutes.

**ShootToMaim** · 03-21-2007, 05:57 PM

looks great man I am using a 1000w hps, 4x4 tray with 4 inch blocks. My question for you is thus:6 floods a day??? I only flood when the blocks have dried out which is once at the beginning of each day