OK so today i went to the beach and it was a saltwater beach and i picked up alot of shells and driftwood. well i have a freshwater 20 gallon aquarium and was wondering if i could use this stuff in my tank or would it be at harm
Personally, I would not use any seashells in a freshwater aquarium as the shells might leach calcium or something else that could change your water chemistry. If you would like to use the driftwood, then you should boil it to remove any impurities. And, then let it soak for several days afterward to ensure there is nothing that could mess with your tank.