Cooking Dry Rock - Vinegar Question

[chatyak]

You should be almost there. I did the last change, went back in a couple of days and was surprised it was clear. Yours may be taking a little longer as it appears that you were a little more aggresive with the vinegar than me.

One thing I would do is dry brush the rock once it's dried out again before you aquascape. I used a little more epoxy than needed as a result of the surface being a little loose in some spots.

I am on my 4th water bin change now.... dunk/swish/scrape etc... hands are actually bloody from holding the rock :headwally: Will see how clear it is after another couple days of rinsing....

 

[Telaverus]

I am on my 4th water bin change now.... dunk/swish/scrape etc... hands are actually bloody from holding the rock :headwally: Will see how clear it is after another couple days of rinsing....

I would not scrape anymore. Just rinse. I think you could scrape this stuff forever and forever have cloudy water.

 

[bertoni]

I'd use gloves. Bleeding hands sounds like an infection risk to me.

 

[Telaverus]

Chatyak, I just came across this in another thread...

RO water threw me a bit. There is a reason to use salt water .Second thought after a cup of coffee.
The rock will start to dissolve at ph below7.7 ,as is the case with ro water. The rock is primarily calcium carbonate. These crystals contain some phosphate bound in them as PO4 binds to carbonate in lieu of calcium in some of them when the rock is made by calcifying organisms.This is why it's harmful to them in excess. So dissolving the rock releases PO4 that wouldn't otherwise leach as these crystals dissolve.
The lanthanum in higher ph water will just pull more loosely bound PO4(probably mostly HPO4 and H2PO4 which have lower negative charges than PO4) from the surface which is what leaches in a reef tank . The aim is to remove the surface stuff without releasing the embedded PO4. SO, I'd definitely use the salt water as noted in post #10 to avoid melting the rock .

Bring your ph up, your water will always be cloudy if you are disolving your rock. My last bucket that ended up clear actually had about a cup of salt in 10 gallons of RO, I just threw it in there instead of down the drain as I had left it in my measuring cup overnight, this was probably just enough to bring my ph up so that I wasn't disolving my rock anymore.

 

[bertoni]

That quote isn't particularly accurate. A very small amount of live rock will dissolve in RO/DI water, but not enough to detect. The pH will then rise substantially.

 

[chatyak]

I would not scrape anymore. Just rinse. I think you could scrape this stuff forever and forever have cloudy water.

Sorry I 'm not sure why I wrote scrape - I meant just using your finger to remove any loose debris after swishing it around - I think that's what removed some of the skin on my finger - I didn't think infection could be a risk with dry rock in RO/DI.

 

[chatyak]

Chatyak, I just came across this in another thread...



Bring your ph up, your water will always be cloudy if you are disolving your rock. My last bucket that ended up clear actually had about a cup of salt in 10 gallons of RO, I just threw it in there instead of down the drain as I had left it in my measuring cup overnight, this was probably just enough to bring my ph up so that I wasn't disolving my rock anymore.

I'm a bit confused on this and what bertoni is saying - are you saying that by soaking rock in ro/di - the rock itself will always dissolve, thus leaving cloudy water - even if the rock is clean? I have never come across this before.

By mixing the rock in saltwater then - this won't happen? I'm running a big powerhead (koralia 8 i think) in a 20 gallon brute bin at the moment with ro/di....

 

[chatyak]

That quote isn't particularly accurate. A very small amount of live rock will dissolve in RO/DI water, but not enough to detect. The pH will then rise substantially.

You are saying that the rock will not dissolve then and if it does, only a small amount - then that dissolved rock amount will raise the ph anyways?


Adding salt mix raises ph.. I guess that is true isn't it - didn't even think of it.

 

[chatyak]

On a side note - when coraline algae covers the rock - doesn't it cover the bacteria surface needed for denitrification? Never thought about it.

 

[Telaverus]

That quote isn't particularly accurate. A very small amount of live rock will dissolve in RO/DI water, but not enough to detect. The pH will then rise substantially.

Yeh, there is a lot more that I was thinking that was left out. Having just gone through the same process as Chatyak, I'm thinking he is looking for the same thing I was, and that's crystal clear water with rocks in it. Eliminating all the variables that cause cloudy water was on my mind more so than disolving rock.

Also, this rock is very "sandy" if you will, it has a lot of fine particles, it's almost like it was made with sand and glue at the surface. Perhaps a result of some pretreatment with muriatic acid by the suplier? Chatyak, did you order this stuff from Go R*** in Quebec?

Bertoni, I have much respect for you, I enjoy following your responses, I've learned much from you.

 

[Randy Holmes-Farley]

Calcium carbonate does dissolve in pure fresh water. But only a little dissolves before the pH rises and stops further dissolution. The water won't become cloudy due to dissolving calcium carbonate, since that is clear.

Cloudiness would be particulates of some sort, either some undissolved calcium carbonate, or aggregated organic matter, or even bacteria.

 

[tmz]

I don't remember the context of the quote but the rock will dissolve in low ph water. How much obviously depends on the volume of water and it's it's ph , the volume of rock and time.. I once put a seashell in a freshwater tank and couldn't figure out why the tank was cloudy week after week no matter how much water I changed.

 

[Telaverus]

I'm in over my head :hmm3:

Tom, you're on my list of mentors, thanks to people like you, Randy and Bertoni this hobby is doable and more affordable :thumbsup:

 

[tmz]

Thanks Televarus,
Randy has the keys to reef chemistry; no doubt about it. When in doubt I'd listen to him. I pitch in where I can.

 

[zero26]

I have 50 lbs of Marco Rock, Key Largo dry rock soaking in a tote of RO/DI water, since Monday. All I did was scrub and rinse with tap water. For me the water was never cloudy and is currently clear.

 

[tmz]

I think if the water gets cloudy it could be an indirect result of dissolving calcium carbonate . Every time the water is changed more low ph fresh water is added.
Perhaps as some crystals dissolve particles of undissolved calcium carbonate break loose and get into the water column and cloud it. It could also be organics or bacteria as noted especially with vinegar in use.

Personally, I prefer to cure dry rock in salt water to limit even small amounts of dissolution and to provide a marine environment to give nitrifying and denitrifying bacteria a headstart. I don't change the water but add some lanthanum chloride to keep the curing water near 0 PO4 if necessary.

 

[zero26]

Tmz,

What is lanthanum chloride?

I think I am gonna try to cure this dry rock with live rock to seed it. Since there is no rush to add this rock to my system I am going to try and cure this for months, maybe even adding a light to it to start some coralline growth.

I just don't want to introduce any P04 to my tank and fuel any algae growth. Already been down that road and do not plan on going down it again.

Thoughts?

 

[chatyak]

Calcium carbonate does dissolve in pure fresh water. But only a little dissolves before the pH rises and stops further dissolution. The water won't become cloudy due to dissolving calcium carbonate, since that is clear.

Cloudiness would be particulates of some sort, either some undissolved calcium carbonate, or aggregated organic matter, or even bacteria.

Wouldn't the ph drop again though? Ex) Rock dissolves - ph rises.... after time ph drops - rock dissolves - ph rises etc...

I don't see how much more can come off the rock honestly. I have used vinegar and water, 100% vinegar, and tons of dunks / swishes / and 4 times cleaning out the brute bin with fresh ro/di water - and it was clean dry rock to begin with.


I'm going to use saltwater and see how cloudy it gets.

 

[chatyak]

I think if the water gets cloudy it could be an indirect result of dissolving calcium carbonate . Every time the water is changed more low ph fresh water is added.
Perhaps as some crystals dissolve particles of undissolved calcium carbonate break loose and get into the water column and cloud it. It could also be organics or bacteria as noted especially with vinegar in use.

Personally, I prefer to cure dry rock in salt water to limit even small amounts of dissolution and to provide a marine environment to give nitrifying and denitrifying bacteria a headstart. I don't change the water but add some lanthanum chloride to keep the curing water near 0 PO4 if necessary.

Congrats on your TOTM - I am just over the "bridge" from you :spin2:

I will be adding salwater today - it is "clear" from the mixing bin - so we'll see how clear it stays with the rocks...


I could also measure the PH of the ro/di with my apex ph probe.... dipping it in ro/di for a few minutes shouldn't effect the probe correct?

 

[chatyak]

Cloudiness would be particulates of some sort, either some undissolved calcium carbonate, or aggregated organic matter, or even bacteria.

Are you saying then, that technically I can keep adding/changing RO-DI water to the brute bin, and it SHOULD be clear at some point?