Muriatic Acid dip?

[Lateral72]

I theory, it has to do something for phosphates. Think of all the dried algae on the outside of the rock, there is a bunch of phosphates locked in that stuff, so at a minimum it will get rid of that stuff. I doubt it will pull phosphates out of the rock, but definitely remove the dried algae.

 

[crackers]

I have used this method many times with great results. Whenever I take rock out I always acid wash it and you would be amazed at how much debris is in the liquid after the soak is done. I have used a little different method also. I read to use a 10 parts water and 1 part acid and it seems plenty strong and just soak for about an hour. After the soak I usually spray them off with a water hose to remove excess debris. If your thinking why use tapwater to wash them because it has phosphate in it I thought the same thing but was told that it wouldn't pick up enough phosphate to make any difference. The acid cleans out the pores of the rock just like etching a cement garage floor before putting down an epoxy coating.

 

[Young Frankenstein]

I have used this method many times with great results. Whenever I take rock out I always acid wash it and you would be amazed at how much debris is in the liquid after the soak is done. I have used a little different method also. I read to use a 10 parts water and 1 part acid and it seems plenty strong and just soak for about an hour. After the soak I usually spray them off with a water hose to remove excess debris. If your thinking why use tapwater to wash them because it has phosphate in it I thought the same thing but was told that it wouldn't pick up enough phosphate to make any difference. The acid cleans out the pores of the rock just like etching a cement garage floor before putting down an epoxy coating.

+1 works great for me, was Little scared using it in the beginning.