I went to test my ph in my 125g with freshly added cichlids and it was at 8.4ph the only thing I did recently was add plants on the top of the tank. Its been a few days and I'm always checking parameters on this tank because everything has been cycled and the fish are added and this is all my first time doing this. But today I went to test everything which checked out perfectly but my ph dropped to 7.4ph? Any thoughts on would could be the issue? Could it be the plants?