Plant drooping after watering and end of light cycle, growing in coco pics

Ok so im growing in slacker by botanicare essentially a high pith coco amended with all premium organics, amd perlite, some solica based rock they have, for added drainage, and some nemificial micros, everything looks great i have plants in 5 gallon pots and are about 1 month old from sprouting to surface as of today, they seem to be slow growers and they are fruity juicy chronic and purple l.a confidential....anyways, just them under a 1000 watt metal halide light 11 days ago and they are still pretty small.....i was watering ebery 3 days with half a liter..but seemed to be overwatering, so now i have waited 5 days to water and gave them 2 liters with runoff instead of small watering more frequently..anyways, now towards the end of the day a few of the purple la s seem to droop significantly and i think the roots have not reached the bottom of pot yet so they are showing symptoms of overwatering, right after i watered after waiting 5 days they were drooping 10 minutes after too! My question is at this stage of poor root to pot size ratio, should i be watering more frequent with small amount or large watering say, once a week for the next 2 weeks, never grown in coco based medium, by the way no peat or anything coco is the main ingrediant besides organic materials, i do kjow coco should habe runoff, but with roots not at the bottommof the pot yet what should i do? Check this link with pics i dont know how to embed sry for typing im a tab... https://www.dropbox.com/sc/2nx5ezvt657d3xc/OW3UKxcdri

Good question. I would recommend in the future to start in a smaller pot and graduate up when the roots take over the pots. 1 gallon to 3 gallon to 5 gallon. Now I guess you will have to water a little and wait til the water is completely gone before watering again. Also, I dont know why but I get the impression that the light is far from the plants. Keep them close for 2 reasons. One is it will allow for evaporation of water in the pots.

if they "perk" in the morning and "droop" in the pm just before lights off thats totally normal . but if droopy all day look into uppotting or spoon feeding water in a small cone around the plant for the first two to three waterings till you get sum mass

Thanks both fo3 th3 replys, i tried the half liter every 3 days thing and th3 roots still could not tak3 it in, now i will try and fully saturate, and just be patient until the water is fully gone, sseems like it may be a week or so, and yes lights are far awat thats a good hunch, i wanted good coverage but i just lowered it after your comment ,!