Help Me with Muratic Acid

[reefgeezer]

Hi all. It's finally time to start my tank over. It has long suffered the results of my learning curve and really needs a new start. I have about 45 lbs of live rock I'd like to reuse, but I don't want the detritus creating critters, pests, bound phosphates, and plants/macro algaes it has collected over the years. I really don't want to put one piece of rock back into the tank unless it is completely lifeless and free of bound phosphates.

To that end I would like to treat the rock in muratic acid. Can someone please tell me the process for doing that? I'd also like to know if I'm expecting too much from the process. I am hoping to create lifeless rock that won't leach its bound phosphates when I set up my new tank. Is that "do-able" with Muratic acid?

Thanks in advance for the advice.

[blanden.adam]

Sure thing, here's an abbreviate protocol for regenerating live rock (well, at least making it clean dry rock anyway).

1) place the rocks in a container of a bleach/water mixture with a small powerhead for 24 hours (never really bothered to measure, but you will see it working. After 24 hours the rock should look white

2) rinse the rock off well and let it dry in the sun or with a fan for 2 days

3) Submerge the rock in a 1:10 solution of Muriatic Acid/RO/DI for 15 minutes with a powerhead. Please take note of SAFETY PRECAUTIONS: Always add acid to water, never water to acid. This is to prevent the heat of dilution from causing the acid to boil and splash you or melt your container. Also, always to this in a well ventilated area as the gaseous HCl is toxic and the resultant CO2 will decrease the oxygen concentration in the area. Wear nitrile gloves, eye glasses, closed toed shoes, and clothes you don't care about. Have ready access to running water in case of splashes or burns.

4) Add baking soda to nutralize the acid. Be generous here, keep adding until the bubbling stops then add some more.

5) rinse the water well with RO/DI, and let dry.

6) you're done!

[tmz]

^ +1 That was easy. Thanks Adam.

[dkeller_nc]

One comment to add to Adam's protocol: it's probably best to get your HCl from a pool supply outlet. The muriatic acid (HCl) sold in home stores is intended for concrete etching, and is highly impure. Typically impurities include metals of all sorts, not something you typically want in a reef.

I should mention that this is speculation - exactly how much metallic contamination is in the home-store acid will vary depending on the manufacturer's batch, and whether or not those metallic contaminants will remain on your rock in high enough concentrations to cause a problem is debateable.

But given that the cost difference b/t the two sources isn't very high, it might pay to be cautious.

[reefgeezer]

Thanks everyone. I think now I'm ready to give it a shot.

[dkeller_nc]

One last comment - do not even consider doing this inside. Adding concentrated HCl to water will generate some amount of hydrogen chloride gas, and getting a snootful of this will burn your sinuses. Adding hydrochloric acid to bleach will generate chlorine gas - again, not something you want to breathe, but no big deal if you do it outside.

I mention this because of your location - you may have to wait for the weather to improve b/c of sub-freezing temperatures, but it beats doing it inside.

[reefgeezer]

One last comment - do not even consider doing this inside... I mention this because of your location - you may have to wait for the weather to improve b/c of sub-freezing temperatures, but it beats doing it inside.

Yea, I planned on waiting until the weather warms. It's stupid cold right now, but will be back to 50 or so soon. Ah-Ah Kansas! Thanks for the warning.

[Dr. X]

Hi all. It's finally time to start my tank over. It has long suffered the results of my learning curve and really needs a new start. I have about 45 lbs of live rock I'd like to reuse, but I don't want the detritus creating critters, pests, bound phosphates, and plants/macro algaes it has collected over the years. I really don't want to put one piece of rock back into the tank unless it is completely lifeless and free of bound phosphates.

To that end I would like to treat the rock in muratic acid. Can someone please tell me the process for doing that? I'd also like to know if I'm expecting too much from the process. I am hoping to create lifeless rock that won't leach its bound phosphates when I set up my new tank. Is that "do-able" with Muratic acid?

Thanks in advance for the advice.

I'm in your boat. Look here:

http://www.reefcentral.com/forums/showthread.php?t=1914426&page=10

[reefgeezer]

I'm in your boat. Look here:

http://www.reefcentral.com/forums/showthread.php?t=1914426&page=10

Thanks for the link. I remember reading it as it was posted. I feel your pain. If it's a pest I probably have it! Luckily, none ever got out of control, but I'm really tired of fighting the battles.

In addition to the pests, a general reset is needed. This is the tank I learned with. I really want to correct a bunch of things I didn't know to do when I set this tank up in 2009. I thought I was pretty up on things then. Thanks to experience and RC, I know how wrong I was now.

[reefgeezer]

All the rock from the tank and a bunch that was sitting dry in a bucket are now soaking in bleach water in the master bath. Yep... in the jacuzzi tub...and Yep, the wife's not happy.

Maybe I'll add having rocks soaking the bathtub to the "You might be a Reefneck if" thread.

[Dr. X]

Good luck, John. Let us know how it goes.

Turns out there are a couple of other threads on this topic, though the one I linked to above is the most comprehensive I've found. I just finished reading all 484 posts last night - whew. Learned a few things, though...

[reefgeezer]

WOW! Put 40 lbs or so of dead rock in 10 gallons of ro/di in a 30 gallon Brute and and add 1 gallon of acid. What a foam fest... at least initially. Maybe doing it on the back deck was not a good idea. Thank god for baking soda!

[reefgeezer]

Over 10 lbs of baking soda later... pH about 6 and draining the brute to the storm sewer. I had to make a baking soda run! I never imagined it would take that much. I guess maybe I used a lb or so of that around the bottom of the Brute to protect the deck during the initial foam-over.

[E Rosewater]

That's a lot of acid.

[reefgeezer]

That's a lot of acid.

It took 10 gallons of RO/DI water to cover the rock I wanted to clean. So, per Adam directions, I used a gallon of acid for a 1:10 ratio. I added it a little at a time but it still foamed a lot. If I ever do this again, I would use a bigger vessel with a much bigger power head. If I could figure how to do it safely, I might even try to mix the water and acid first then add the rock.

To my wife's dismay, the rock is now in a rinse cycle in the tube. Areas where there was heavy coralline are now white. Areas where there was little or no coralline are just kind of a light tan. Most of the rock appears more porous also.