What is this rock, How to clean?

[CoryWithAKatana]

So I went to my backyard pond and found 2 cool rocks. I live in Florida and we dont get many rocks so this is kinda strange. 

1) Can any fellow Floridians identify what kind of rock this is and is it safe for Aquariums

2) If this rock is safe how do I clean it so its safe for my tank.

[Tlindsey]

On 5/8/2024 at 12:03 PM, CoryWithAKatana said:

So I went to my backyard pond and found 2 cool rocks. I live in Florida and we dont get many rocks so this is kinda strange. 

1) Can any fellow Floridians identify what kind of rock this is and is it safe for Aquariums

2) If this rock is safe how do I clean it so its safe for my tank.

I don't know what kind of rock that is but do a test pour vinegar on the rock. If rock fiss then it contains calcium carbonate.

[CoryWithAKatana]

I just poured Vinegar on it and the rocks did not fizz.

[Beach Cruiser]

Pretty much every native type of rock in South Florida is some type of limestone. That looks like some type of aggregate (mix) containing shells, etc.  It definitely has calcium carbonate in it, but your water is probably pretty hard already so it may not effect much.  It may even be super old concrete, as the early Florida pioneers mixed crushed shells since they didn't have access to regular gravel. St. Augustine is full of old concrete walls with shells.  I'd soak it in a mild bleach solution (12:1 water to regular bleach) overnight & then in straight water for a few days, then let it dry in the sun for a week if you want to be super safe from infection of plants/fish.

Edited May 8 by Beach Cruiser