Did you just water the night before? Sounds like some sort of lock out? Maybe Ph caused? Tell about water and prep of water. Nutes etc: Curly tips are a indicator of over-water, over-nute(too strong). I would Flush with plain Ph'd water that has been bubbling for a day or somehow agitated for a day. Flush about three times amount of pot, use "Final Phase" by AN, or something like "FloraKleen" by GH. after flush start with 1/2 nutes. then hopefully it's going again!