Use Reverse Osmosis water. Stay away from other types of bottled water. The PH of RO water and other types can have a weird ph reading. Usually lower then normal. Some Deer Park RO water read 3.9 ph I believe but now I just use tap and let it sit for 3 days to get rid of the chlorine. Saves $$$ on cal-mag too. What is the ppm of your tap water. If less then 200 use it. You can get a water report telling everything in the water online from your water company. What is the temp of the growing area? also they don't need a lot of light at that stage so if heat is a problem then cut back on a few bulbs.