Snail identification

[Trevir]

hoping to use some expertise of the veterans. 
 

I have one nerite snail (featured in first photo) I had two, the other died right after Christmas, the next day I noticed these little dots on the glass and thought it was my corydora laying eggs again, when I noticed they were moving I was both excited and anxious. I dont have brackish water. The other thing is I havent added anything to my tank since at least July, I have never had more than 2 snails and I specifically chose nerites so I wouldn’t have to worry about babies. 
 

How do identify these little guys before they get big enough to actually effect the tank ecosystem? 
 

With 50% of my nerites out of commission my algae is already getting out of control so I am trying to decide what to do with these guys, let them live or introduce something that can take care of invaders(as rare as they may be) and balance the system to deal with the additional bio load. 
 

10gal corner tank with rounded front face so images are a little distorted and its hard to get an angle of the top of one, plus they dont have a twist formed yet. Just kinda domed and pointy. 
 

[Trevir]

[Ninjoma]

My guess is limpets or bladder snails. 

[Trevir]

Any idea how long their eggs could have been dormant on a plant? Its been 8 months since we added anything. 

[Ninjoma]

On 1/7/2023 at 10:25 PM, Trevir said:

Any idea how long their eggs could have been dormant on a plant? Its been 8 months since we added anything. 

I don't have any specific knowledge on that, sorry. 

[Cinnebuns]

On 1/8/2023 at 12:25 AM, Trevir said:

Any idea how long their eggs could have been dormant on a plant? Its been 8 months since we added anything. 

I honestly have been curious about limpets in my tank too. I had a decent amount for awhile and they randomly disappeared. Now they reappeared and I can't nail down a reason why. I might do more research or even make a seperate forum post to learn more. I'll let you know what I find. 

[Katherine]

I'm thinking limpets too. 

[Biotope Biologist]

Yup freshwater limpets.
 

They do go through population swings in the freshwater aquarium. And they are so tiny they are hard to notice. They are also likely nocturnal. They will max out at about 7mm and although they chew on plants and algae, they do not seem to be harmful to plants.

[Trevir]

So it is possible that my 2 nerites kept the population small and in the substrate? 

[Cinnebuns]

On 1/8/2023 at 12:08 PM, Trevir said:

So it is possible that my 2 nerites kept the population small and in the substrate? 

The small amount of reading did suggest they burrow a lot. If the nerites did it would be because they ate up the algae around the tank already not because they are avoiding them I would assume. I have about 6 nerites in my tank but I still find limpets around high algae areas. Limpets also eat detritus whereas nerites rarely if ever do. 

[Trevir]

So in other words they’re not bad to have in the tank and they can help as long as their numbers stay balanced. 

[Trevir]

So in other words they’re not bad to have in the tank and they can help as long as their numbers stay balanced. 

[Cinnebuns]

On 1/8/2023 at 5:22 PM, Trevir said:

So in other words they’re not bad to have in the tank and they can help as long as their numbers stay balanced. 

Exactly. The only "bad" part about them is if you can't stand to look at them really. Which can be a deal breaker for some people because an aquarium can be like a living painting. Ecosystem wise tho they are a valuable addition. 

[Odd Duck]

Yep, another to confirm freshwater limpets.  They only get 2-3 mm and I’ve never had them cause any issues.  Many fish will eat them or at least they disappear in most tanks that have any fish that pick at things in the tank (vs. just eating floating foods).  If you keep scraping the glass, their numbers will go down, too.