# Calcium good for Aquarium?



## luffypets (Aug 10, 2019)

Hello everyone

I have a 40 gallon tank with few bettas in it. Please advise if I can add some calcium rocks in it?


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## FishTankExpert (Jun 19, 2021)

I wouldn't recommend it. Especially for Betta Fish I have found that calcium could possibly kill them over time.


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