By the Sea Shore

[vanalisa]

I have lots of various shells in my tiny collection. Some actually have holes.
What do I need to watch out for regarding putting shells in our aquariums?

 

[JuiceBox52 7]

The shells will raise the ph. Also they wont look pretty for too long as they will start dissolving

 

[CassCats]

Generally, keep them for species needing harder water. And try to stick with freshwater shells.

 

[Retired Viking]

I agree with the above remarks and also check for shape edges on the shells.

 

[Byron]

Agree with above members. Two things to add...if you collected these yourself from the shore of a watercourse or lake/ocean, give them a good scrub to ensure there are no bird dropping and similar, as these can spread disease to fish and you. If the shells were purchased, make sure they have no paints/dyes/coatings that can leech off the shells and poison fish and invertebrates.

 

[Colin_T]

Shell are fine but might raise the pH a bit if there are lots of shells in the tank.

If the shells start dissolving, then the pH of the water is below 7.0 and the shells are neutralising the acids in the water. This is normal.

The small round holes in the shells are caused by octopus grinding a hole in the shell so they can inject venom into the shell and eat the inhabitant. Some star fish also make a hole in the shell when trying to get at the occupant.