Crushed shells are just the normal shells you see on the beach at the shore that are just crushed, right? Like there is nothing different in the mix that makes them good for your kh and ph.

My kh is 2 and the ph in my tank is 7 but the ph in my moms tank is only 5, so I wanted to put some in there. I have some shells that I picked up from beach so I was wondering if I could just put them in the tanks. I think I have a piece of coral too that I could put in but I would need to find it first.

Silver, I would be very cautious when adding anything to the tank that didn't come from a pet store. Shells from the ocean can harbor all kinds of micro organism that could be potential harmful to your fish. Pet stores, especially the ones that have saltwater fish, carry bags of crushed coral in different sizes, and those are sterlized and ready to go into your tank with no danger of harm to your fish.

OK thanks. I have quite a bit of shells from going to the shore over the years and I was just wondering if I would be able to put them in there to help my kh and ph. I'll just have to run to the pet store then