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So I have had my six neon tetras for almost six months, with no problems. They are in there with a mystery snail, a ghost shrimp, java fern, a small bamboo, and another plant that I can't remember the name of. I want to get some new fish for my tank and I can't decide what to get and have found very little info on what goes well with neons. Any help would be appreciated. The ph, nitrates, and nitrites look really good, but I have hard water with 120 water hardness. I know that is a little hard for neons but what type of fish would thrive in that? It is heated, and has a great filtration system, and has an airpump.

I added 6 neons to a fully cycled ten gallon tank, as well as 2 ghost shrimp, and an apple snail. I want to add a few more fish in a month or so. The nitrates ate at 0 so that is not an issue, the ph is 7.5, however the general hardness is 120... I would like a centerpiece/top dwelling fish and some bottom feeders, but I think both would be over stocked, suggestions?