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T5 Seedling Light on 24 hours

Beans have been soaking and tap root is showing. Seeds are in rapid routers under T5 in dome. 72% Humidity 76 F I have the light on 24hours how long should I keep light 24 hours before dialing back to 18 hours? First pair true leaves 2 pair true leaves? Thanks

Don’t matter, Figure out what time you want to start 18/16 Then turn off your 24 when you want your lights shut off give them six hours of sleep. Then turn them back on when you want to start at 18/6 …

Thanks hashone

As soon as the plants have leaves they can be switched to 18/6. I keep them under 24h light until I know all the sprouted seeds have had a chance to see the light. If I start with 18/6 there’s a chance the leaves might sprout in the dark (which there is nothing wrong with).

I start with 24/0 then switch to 18/6 after there are leaves showing. When I switch my lighting schedule I also start to vent my domes or raise my VPD. Bottom heat is great for roots too, so a seedling heat mat is a good tool to have.


Have you ever tried running 11 on 6 off 1 on six off instead of 18/6? It saves a ton on energy.


I haven’t, but doing some more lighting experiments is high on my list of new things to try. Do you keep track of your DLI as you move through your different stages of growth?

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I have done a lot less so lately. I did a lot more the first year. Now I can pretty much know by the par reading and now I have done it so much I know the lights par readings by the distance between the lights and the canopy. I can only do that with my lights I would have to calculate another. You should try that one it has some suprising results


But Par meter are you using? for

I’m looking into buying one of these two at the moment

Sorry damn auto text what par meter are you using , I’m going to buy one of these two

@hashone I have seen the sun system par meter in both of my cousin’s grows. To expensive for me but cousin’s own big farms and that’s what they use if that helps

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