Increase and stabilise ph and kh.

-Natural osyter will slowly dissolve and release carbonates and calcium ions into the water.
-It increase and stabilise the PH and KH over 6 months and prevent dangerous ph crash or swing in aquarium/pond.
-The oyster shells are thoroughly wash and further cleaned to remove any leftover organic residues.
-Suitable for canister filters, internal filters, top filters, trickle filters, pond filtration and sump filtration.