I would like to thank this forum for lots of excellent information. I read a thread (Apr 25,04) about dry nutrients where tailwheel posted a mix (thanks) he was using. For 18 gallons water 75grams fert, 25grams magnesium sulfate, and 45grams calcium nitrate. I have a fifty gallon tank so I increased amounts to 208grams 8-15-36 fert, 69.5grams Mag sulfate, and 125grams calcium nitrate. Question is -- I checked the EC and it is 2100. I have read that the EC should be 2500-3500 for tomatoes at 6.30 ph. How should I adjust my nutrient mix?