Chemistry- copper saturated rocks

[Miami Reef]

Question for @Randy Holmes-Farley

I have rocks saturated with chelated copper.

If I do a 10:1 muriatic acid bath for 30 minutes, will that remove all traces of copper from the rocks, or will there still be a trace amount of copper remaining?

 

[Randy Holmes-Farley Verified Community Expert]

If the rocks are porous, it may not remove copper in the pores, but it should remove copper along the outer edges as it removes the calcium carbonate it is attached to.

One problem is that once the acid has done it's thing, copper may bind again tot eh fresh rock surfaces before you remove it.

 

[Miami Reef]

If the rocks are porous, it may not remove copper in the pores, but it should remove copper along the outer edges as it removes the calcium carbonate it is attached to.

One problem is that once the acid has done it's thing, copper may bind again tot eh fresh rock surfaces before you remove it.

I see. So muriatic acid is not the best for this purpose.

But letting in sit in plain RODI with cuprisorb. Is that going to work to remove all traces of copper in the rocks, or is it better to just start fresh?

 

[Randy Holmes-Farley Verified Community Expert]

I see. So muriatic acid is not the best for this purpose.

But letting in sit in plain RODI with cuprisorb. Is that going to work to remove all traces of copper in the rocks, or is it better to just start fresh?

It is a sensible plan, but it may take a while. Keep the water moving over the rocks and the cuprisorb.

 

[Gp!]

Can't you test it with a Hanna checker to see if you need to soak again? With the prices of rock these days (and just not being able to get the same type anymore) if you have good rock that you like I'd try to save it

 

[Randy Holmes-Farley Verified Community Expert]

Can't you test it with a Hanna checker to see if you need to soak again? With the prices of rock these days (and just not being able to get the same type anymore) if you have good rock that you like I'd try to save it

No, it does not accurately test at low levels.

 

[Miami Reef]

PS: this is for a new build

I do not have corals yet.

Step 1: do a bleach cure prior to limit organics.

Step 2: aquascape

Step 3: Put rocks into new tank and run cuprisorb and phosphate remover for a few weeks.

Step 4: Remove cuprisorb 1 week prior to sending out ICP test

 

[Randy Holmes-Farley Verified Community Expert]

Sounds like a fine plan.

 

[Miami Reef]

I was just about to post in this thread!

In a BRS video, they said it’s fine to do a bleach cure with tap water. Assuming tap water has heavy metals, and also assuming rocks can absorb metals.

Does the addition of bleach detach metals from rocks?

 

[Miami Reef]

I just started the bleach cure today FYI.

 

[Miami Reef]

Also, does bleach directly break down phosphates? Or does it only break down organics on the rocks, which prevent more phosphates from becoming produced, but does nothing for the phosphates already absorbed in the rock?

 

[Randy Holmes-Farley Verified Community Expert]

I was just about to post in this thread!

In a BRS video, they said it’s fine to do a bleach cure with tap water. Assuming tap water has heavy metals, and also assuming rocks can absorb metals.

Does the addition of bleach detach metals from rocks?

Not very effectively, IMO. . It removes organic matter that can have metals in it.

 

[Randy Holmes-Farley Verified Community Expert]

Also, does bleach directly break down phosphates? Or does it only break down organics on the rocks, which prevent more phosphates from becoming produced, but does nothing for the phosphates already absorbed in the rock?

No, bleach does nothing special for phosphate that is bound to calcium carbonate.