Are snails good or bad for a tank?

Hello all, I just have a curious question for you guys. Are snails good or bad for a tank ? do they do anything productive?

 

from my experince they are good and bad. I have a few in a small goldfish tank that I was having a problem with algae and they helped alot. but I also have a 55 gallon planted cumunity tank that got them in off one of the plants. they were small and hard to see in the gravle. they destroyed most of the plants before I was able to get bthem under control. my opinon is that if they are cuasing damage you could get a yoyo loach or 2 and they will help keep them under control. worked great for me only snails I see now are with the goldfish

 

The answer to this largely depends on the type of snail you mean!

Apple/Mystery snails and Nerite snails are kept as pets- I have never had them but I find them quite pretty and am sure they are interesting to own.

MTS do a lot of good things for sand substrate by keeping it well mixed- plus I also think these look cool. I have some and I would categorize them as "good" snails.

Most people hate pond snails. I have some and think they are interesting. However, I have heard of them totally decimating plants, as already mentioned. Personally I don't have much of a problem with them eating plant matter (knock on wood!) except for a few nibbles on the ends of a leaf or two. I would say don't TRY to get pond snails, but if you do, you're not necessarily doomed.

And there are lots of other snails (ramshorns and assassins come to mind) that I know nothing about.

 

I think snails are kind of cool. They clean alge and eat the trash that is left over from over feeding.

The worst ones, as mentioned above, are the pond snails. They can be in live plants. I had a minor problem, not sure where it came from since I don't have live plants but I think it might have came from the water at the LFS.

 

I have 3 mystery snails which are pretty cool looking. They don't really do much - occasionally they will nibble on my plants but I make sure they have zucchinI to eat so they stay away from my plants.

I have 3 pond snails in a jar that I plucked out of the tank ( hitchhikers from plants I bought months ago )
I don't care for pond snails so I am keeping them in this jar with plants and will give them to the lfs.

I was hoping the one MTS snail that I put in my tank over 10 days ago surfaces but so far, haven't seen him! I don't know very much about MTS but they are considered beneficial as they clean up the tank and do their janitorial duties at night.