Cuttle fish bone for calcium?

[Clownshow]

So when I used to keep freshwater tanks I stuck cuttlefish bone in the tank to provide clacium for the snails. I am curious, would the same work in saltwater for corals and snails?

 

[xxkenny90xx]

I'm not familiar with cuttlefish bone but I do have some coral skeletons decomposing in my tank. I imagine the calcium is being sucked right out of them

 

[Randy Holmes-Farley Verified Community Expert]

I'm not familiar with cuttlefish bone but I do have some coral skeletons decomposing in my tank. I imagine the calcium is being sucked right out of them

Are you sure they are dissolving?

Seawater is supersaturated with respect to calcium and carbonate.

The only way calcium carbonate can dissolve is deep in a sand bed or pore where organics are decomposing and lowering the pH. If the pH drops below about pH 7.7, they can begin to slowly dissolve.

 

[Randy Holmes-Farley Verified Community Expert]

So when I used to keep freshwater tanks I stuck cuttlefish bone in the tank to provide clacium for the snails. I am curious, would the same work in saltwater for corals and snails?

Not a good plan, IMO.

Fish bones are a mix of calcium carbonate, calcium phosphate, a mixed material of calcium phosphate and hydroxide (hydroxyapatite) and many organics. They may slowly and uncontrollably release some of these things to the water.

Calcium chloride is very cheap and pure, and there's no reason to not use it when you want to supplement calcium.

 

[xxkenny90xx]

Are you sure they are dissolving?

Seawater is supersaturated with respect to calcium and carbonate.

The only way calcium carbonate can dissolve is deep in a sand bed or pore where organics are decomposing and lowering the pH. If the pH drops below about pH 7.7, they can begin to slowly dissolve.

Lol I have no idea if they're "dissolving". I just see that some of my older skeletons (mainly montis) have gotten thinner and now have big holes in them. I assumed they were dissolving like they would in a reactor, only at a much slower rate.