Hi, i am new to fish keeping my tank was set up about 3 months ago, all was going well then fish died through white spot since then having major problem getting ph correct so purchased proper ph 7.0 i put this product in tank +has since gone cloudy instructions say this is ok + will not harm fish but how long does cloud remain as i have two eheim ex filters running in one of my tanks + a aquamanta efx1200 in the other does not seem to be clearing could someone please advise me as some fish are still alive + would like to save these cheers.