I had this tank where it couldn't house guppies at all.. Slowly one by one will die, but the special thing about it is that, all the males will die first, then the females.. AFR males will get their tails paled then die.. Any advice? Tested pH and tried to increase it, now around 6.5 I had this tank where it couldn't house guppies at all.. Slowly one by one will die, but the special thing about it is that, all the males will die first, then the females.. AFR males will get their tails paled then die.. Any advice? Tested pH and tried to increase it, now around 6.5