Also known as Malaysian livebearing snail (Dr. Axelrod's Mini-Atlas). I got one (just one) of these snails when I was buying other fish and didn't know I had it until I released the fish into the tank. I saw it drop to the bottom and burrow into the gravel. I didn't think I would ever see it again. A few months later, after feeding the fish I thought it looked like the gravel was moving. I got up and looked and there were hundreds of them. I don't know about some of the other comments I read, but these other people must have had a lot of plants and snail eaters, because my snails killed every plant (but the toughest) in my tank by eating the roots. I had no snail eaters in the tank, but I have added a few and they haven't even put a dent in the population. My hundreds have turned into thousands and have made it into my other tanks. They get into filters and sometimes jam the pump. I can't get rid of these snails. Chemicals don't kill all of them because they live deep in the gravel. I have had people (one person, an aquarium store owner) ask for some of these snails and I just can't bring myself to give them any because of the problems I have had with them. On the bright side they do keep the gavel clean, but they really don't do much about algae.
I recently went to a fish store and was looking at the live plant tanks and saw an adult Malaysian trumpet snail. I asked if they sold them and they said they have tons of them that came in through plant shipments and they would just give it to me since they cannot sell them. I thought it looked cool and I brought it home with a live plant. Within 2 days it has cleaned my gravel and has not eaten my plant.
I started off with about 5 of these guys, within a month or two they had multiplied to about 70. You wouldn't believe it looking at the tank, but leave the lights off for 10 minutes and they're all over everything! Although said to be nocturnal, many come out in the day. I added 3 Clown Loaches forgetting that they fed on snails, however this turned out to not be an issue as the snails daytime habits changed. They rarely came out in the day, unlike before the Loaches were added. These guys are good at eating algae for planted tanks, but don't expect them to do all the cleaning. In particular, hair alage is prone to growing, but they are a good addition and are a good bargain.
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