Hi, I have done a couple of large water changes in the last three days to lower my Nitrates but since doing so I have lost 4 fish in the process. All parametters are ok but I am wondering if these deaths are casued by the lowering of PH. Normally my tank is at 8-8.2ph tap water is 7. I am thinking that becasue I done 2 50% water changes in a day I dropped the ph to fast. I havent really seen any symptons as by the time I look in the tank the fish are already dead. I only saw one which was a Bol Ram that couldnt keep its balance in the water and it seems only the fins either side were working so he could propell but had no co ordination.