Okay so, I need some help with aquarium decor. I bought these rocks by the pound from my local fish store (that is honestly a joke) and I was told all of these rocks are safe to be in an aquarium. However, the cave rocks are flaking and soft. I have apistogramas, and I know they prefer soft acidic water. Am I correct in thinking these probably screw up the ph and hardness of my tank flaking off? Would you just remove them? Yes I know the algae is covering them pretty bad, but my heater quit and my fish were stressed and I didn’t want to remove the rocks and scrub them and stress everyone worse!