Thats 1 of the probs with hydro is keeping the res water cool enough, good luck bro....I do hempy buckets which is the easiest way to do hydro..its just a 2-5gallon bucket with a 7/16 hole put into the bucket 2 inches up from the bottom and this is ur res and u dont have to worry bout res changes or temp of the water/res..240g of 6 autos my first run/grow,,Very easy and u cant over water..