I'm growing some sativas that can get to massive heights, if you watch any of the greenhouse seed videos on youtube, one of them was about 9 feet. I don't have that much height in my rooms. I'm just using the 4 inch rw on top of a 6 inch to keep the root growth down, which in turn will keep their height down. As far as killing the algae growth, I had a cube show signs, so I ripped the infected areas, I didn't notice any growth under what I ripped off, so I think that did the trick. If you can afford it, grab some hydroguard, it helps kill microbes or whatever they're called, add that into your res.

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My Green House Seed Co. Grow

ive bough some hydroton, as well as hygrozyme..... i just changed the water and added half dose of nutrients, also i changed the watering schedule to only twice a day for 30 minutes each. i guess i will see in a couple of days how my plants are doing!

i rinsed the hydroton, but it still seems to be leaving a brown residue..... normal ?

yeah, it's the residue washing off, it's normal. I meant hydroguard btw, not hydroton, hope you knew what I meant.

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My Green House Seed Co. Grow

heres a tip u u dont want to grow in ur house and u gotta alota land t a plant then a corn plant then anotherplant trust me this works

Im having trouble with the ph, and intake of nutrients of my plants as well as not watering them too much.... I think tommorow i will test the ph of the water comming out of the rockwool instead of the ph in the resevoir....
i just did some reading and turns out rockwool is not so ph stable..... even though i did soak it for 24 hours....

not sure if any1 pointed this out cause didnt read it all but i grow in expanded clay and rw and i found for first say 3 weeks 1s a day was enough then go to 2 times a day for 3-6 weeks and now im on 3 times a day but im growing in expanded clay aswell as rw so u prob wont even need to water that much

thanks smoke and fly, no one told me, and well now im at once a day, i started out 6 times a day, realized it was wayy to much, went down to 3, then 2, now im at once a day, the rockwool really holds its water !!