Watering seedlings in canna clay pebbles in net pots

First post be gentle! I had a search didnt find the answer but it will be out there.

I have some seedlings in rootit cubes (not rockwool) that have been potted in net pots with canna clay pebbles. These are to be put into a DWC system but I need to veg them longer to take clones before I put them straight into the room of bloom.

I know I should have put them in soil then put the clones into the DWC but i've since filled space so I'm stuck with 3 diff strains in net pots that I want to keep alive to get a clone or two from each, so my question is how often should I water them? I've burried the sponge so I can't tell when it dries out but the pebbles seem to be drying out within 24 hours. Should I remove and put in soil?

They are under a T5 prop light on 18 hrs room is 65of lights off, 79of lights on and Rh at 40% lights on.

Probably about every 4 hours in clay pellets. No watering when lights are off, just one watering about an hour before lights out would be fine.

What do you mean by clay pebbles in air pots? Do you mean net pots?

Yea net pots my bad.

Thanks Renfro, quick response literally saved my honey cream - I've re-potted all into soil as I'd forget to water. 2 were fine but the sponges were drier than i'd like, one was bone dry just caught in time.