Acid wash question.

[Kershaw]

Hello.

I have never use muratic acid on reef rock before. So have some very old reef rock that was tried out about 3.5 years ago. So today I filled a Rubbermaid trash can with rock, water then acid. I Used about 2 cups of acid in a 20 gal trash can. An hour later I put baking soda in it to neutralize it.

my question is. Is the rock supposed to be noticeably clean? Or should it still look dirty. Because as far as I can tell the acid did nothing. Thanks

 

[PatW]

The acid certainly did do something.

Calcium Carbonate + HCl (muriatic acid) goes to CO2 and CaCl2 And H20. What the acid does is remove the top layer of rock, Put in enough acid and you will have no rock at all. The idea behind acid washing is that the top layer of rock is most likely to have unwanted stuff attached to it. So removing it is a good thing. If you want white rock, giving it a bleach rinse might do it. Just be sure to rinse it thoroughly after the bleach. But having bright white rock is not a big deal because one your rock will get encrusted with algae before long anyway.

 

[KStatefan]

2 cups does not seem like it would have been a high enough concentration to do anything.

 

[homer1475]

Did it foam up at all when you dumped the acid in?

I agree 2C in probably 15 gallons of water more then likely diluted it too much. When I did 50# of rock, I used a 20G brute and about half a gallon of acid. Foamed up like heck too.

 

[aSaltyKlown]

Not enough acid. You would want about a 10:1 ratio. It can also reduce the weight of the rock up to 25%.

 

[Kershaw]

It did foam. But very slowly. I’m not looking for white rock. I’m Looking to remove bound phosphate. I did bleach the rock a few days ago.