How often to flood 2x4 flood tray under 24/7 lighting ?

i have a 2x4 flood tray under a 400 watt metal halide(600 hps for flower).
The plants are in 6" net pots with clay pebbles and the 1" Rockwool cubes on top they were started in.

The lights will be running 24/7. The room stays 72-76 degrees, pretty low humidity. How often should I flood the table? The roots are already established, pouring out the bottom of the Rockwool.

Beezcheeze said:

i have a 2x4 flood tray under a 400 watt metal halide(600 hps for flower).
The plants are in 6" net pots with clay pebbles and the 1" Rockwool cubes on top they were started in.

The lights will be running 24/7. The room stays 72-76 degrees, pretty low humidity. How often should I flood the table? The roots are already established, pouring out the bottom of the Rockwool.

Click to expand...

How big are the plants? It's basically impossible to overwater hydroton. Hence you can use them for areoponics, nft, dwc and tables. But you should be safe at 6 times a day. Wait until the water hits the over flow and then turn off the pump. I know on 4x4's it took about 7 mins to flood my tables, but I use 3 extensions on my overflow.

Alter the flood times by the plants health. 6 times a day should be used with larger teen about 8 to 10" tall give or take..

I've gotta trim one spacer down and will be using 2 1/2 spacer lengths. The plants are only 8" tall and 2-3 sets of leaves. But the roots are pouring out the bottom of the Rockwool 3-4" into the hydroton.
I'll start with what you reccomend, thank you!

So this is my first flood table and here's what I ended up doing.

The water pump I had is too strong to use the smaller flood hole as the inlet because the water shoots up and out of the tray.

So I just used the smaller flood drain hole for the overflow and the larger hole for the water pump input.
The 2x4 tray floods in 2 min 30 seconds so I am running on for 3 minutes, 6 times a day. It takes about 7 minutes to drain completely, so 10 minutes total wet time.

It seems to work okay this way so gonna stick with it for now.

Here's some pics of the plants. There's a few plants with funny business going on. Hoping they make it back just fine after the next few waterings.

The one plant I showed a close up of has the leaf edges curling up. It's the only one tho. Think it's a potassium deff..

I had a thought, when the tray floods, all of the water is exposed to light. That's 6 times a day at about 10 min each time that the water is exposed to light. Will this cause any probs? Thank you

Beezcheeze said:

The one plant I showed a close up of has the leaf edges curling up. It's the only one tho. Think it's a potassium deff..

I had a thought, when the tray floods, all of the water is exposed to light. That's 6 times a day at about 10 min each time that the water is exposed to light. Will this cause any probs? Thank you

Click to expand...

Naw you should be fine. Just do res changes every 7 to 10 days until they get big. Once they get big in flower they will drink so much you shouldn't even need to change the res, just top her off.

Also I suggest using small sub pumps instead of airstones in your res.

When I ran tables I use to freeze two 2 liter bottles and throw them in my 50 gallon res every 8 hours to keep my water temps down.

Lol good idea on the tub screen for your drainage. I've never seen that done before..

Also I've seen people fill the whole tray with hydroton. In theory it should be better than using pots. You have more room for the roots and it keeps the light off the water.

What nutes?
Tap or Ro?
Res temps?
Ppms?

I would hate to have to clean that much hydroton tho lol.
And moving the plants is nice for now. Any other ideas for that issue?

I do have a small water pump I can set up instead of the air pump. Just enough to keep some surface agitation and mix the water constantly. Good idea?
And yea the screen works pretty good. Had a few laying around luckily.