Growing black widow just switched to flower 2nd week. My ph keeps dropping from 5.8 to 4.5-4.9 over night. I found my filter got clogged burnt up fan must had been dustier n my shop than i thought. 5x5 Grow tent. Im growing using distilled water my tap has over 420 ppms. I have been using all GH nutes. I changed out water ran GH Flora clean through it was fine for a day now its back again. My plants were so beautiful now im loosing them. Its been going on for over a week. I keep using GH ph up to try and keep it back up. Please help…