Hi people.
I have some large Ramshorns in my pond. My pond is tiny, it has no fish but a frog, many daphnia and loads of snails. My ramshorn snails are about 1'1/2 inches. They have been brilliant at eating the algae and I love them a lot. Recently I have noticed that some of them have algae growing on them and some have their shells deteriating. I have heard that they need calcium, can I use crushed egg shells as a supplement? Also I don't want to use any chemicals at all. Any help greatly appreciated.