Will clams kill my tank?

No... a dead anemone still takes the cake in my book and you can't net it out most of the time lol.. though it aint FW
 
The guy at my LFS says his clams get bought up quickly. He says Bio teachers set up 5-10 gallon tanks, filtered with only clams, stock it with live bearers and someplants, and by the end of the year the tank is still doing great.
 
Alright I will skip the clams guys thanks alot!
 
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