Bleach vs Acid
- Thread starter bheron
- Start date
On Saturday I soaked all the reef bones in a vinegar mix for 1 hour. I used a mix of 4:1 (RO water : vinegar).
I weighed 2 pieces of rock to see how much rock was dissolved in a 20 minutes soak of acid.
I used Hydrochloric Acid at a ratio of 10:1 (RO water : H.A.)
Once I added the rock to the mixture this is what happens
After 20 minutes of soaking I removed the foam from on top. This is what was floating around at the surface
Like I said I weighed a few pieces of rock to see how much dissolved.
Before - 1,284g
After - 1,084g
Before - 635g
After - 475g
After soaking the bones I let them soak in more fresh RO water for a few hours.
Then I washed all the bones in RO shaking them getting as much rubbish out as possible.
This is the water after the first wash in RO.
If I was to ever do this again I might be tempted to use bleach. There was still a fair amount of organics on the rocks and think the bleach would of helped remove them.
Still happy with how they have turned out. They look a lot better.
I weighed 2 pieces of rock to see how much rock was dissolved in a 20 minutes soak of acid.
I used Hydrochloric Acid at a ratio of 10:1 (RO water : H.A.)
Once I added the rock to the mixture this is what happens
After 20 minutes of soaking I removed the foam from on top. This is what was floating around at the surface
Like I said I weighed a few pieces of rock to see how much dissolved.
Before - 1,284g
After - 1,084g
Before - 635g
After - 475g
After soaking the bones I let them soak in more fresh RO water for a few hours.
Then I washed all the bones in RO shaking them getting as much rubbish out as possible.
This is the water after the first wash in RO.
If I was to ever do this again I might be tempted to use bleach. There was still a fair amount of organics on the rocks and think the bleach would of helped remove them.
Still happy with how they have turned out. They look a lot better.
Thanks also have a phosphate reading from before. Its a lot higher than i expected! Will post both the before and after at the same time though.
Yea i done the vinegar as a weak bath hoping the rock would absorb a little more and have a while to soak it all in. I added a power head as well to get a little water movement in there just to mix it all up.
Yea i done the vinegar as a weak bath hoping the rock would absorb a little more and have a while to soak it all in. I added a power head as well to get a little water movement in there just to mix it all up.
blide
Premium Member
Just thought I would thank everyone for their informative posts.
I did the bleach then acid (HCL) bath.
Bleached for 24hrs -> rinsed and air dry for 48hrs
Acid Dip - 10% solution (High Purity HCL)
Rinse - Then a short soak in high alk (baking soda) solution to neutralize acid.
Oh and don't forget to use PPE when messing with this stuff!
I did the bleach then acid (HCL) bath.
Bleached for 24hrs -> rinsed and air dry for 48hrs
Acid Dip - 10% solution (High Purity HCL)
Rinse - Then a short soak in high alk (baking soda) solution to neutralize acid.
Oh and don't forget to use PPE when messing with this stuff!
Do I need to anything else to neutralize the acid? All I have done is soak in the acid for 20 minutes.
Then I let them soak in RODI water for a few hours before rinsing/washing each rock in a tub of 25 litres (6.6 us gallons) RODI. I have put them into a container to soak in RODI water and changed it 5 hours ago (was in there for 24 hours). I will do the same thing again in another 19 hours tomorrow night.
Thanks
Chris
Then I let them soak in RODI water for a few hours before rinsing/washing each rock in a tub of 25 litres (6.6 us gallons) RODI. I have put them into a container to soak in RODI water and changed it 5 hours ago (was in there for 24 hours). I will do the same thing again in another 19 hours tomorrow night.
Thanks
Chris
That's the reason, or part of it. 
Phosphate binds to calcium carbonate surfaces as PO4--- or possibly HPO4--. H3PO4 won't bind at all, and I expect H2PO4-- binds fairly poorly. So lower pH reduces the portion of those things which bind.
Also, low pH will dissolve away the CaCO3 itself, releasing anything that is bound to it.
this has more detail:
Phosphate and the Reef Aquarium
http://reefkeeping.com/issues/2006-09/rhf/index.php
from it (and note the pKas are for seawater, not freshwater):
Figure 2. The structure of inorganic orthophosphate, with a central phosphorus atom (purple) and four oxygen atoms arranged in a tetrahedron. Three of the oxygen atoms can either have an attached proton (green) or be present with a negative charge on the oxygen atom (red). The amount present in each form in seawater varies with pH as indicated.
Phosphate binds to calcium carbonate surfaces as PO4--- or possibly HPO4--. H3PO4 won't bind at all, and I expect H2PO4-- binds fairly poorly. So lower pH reduces the portion of those things which bind.
Also, low pH will dissolve away the CaCO3 itself, releasing anything that is bound to it.
this has more detail:
Phosphate and the Reef Aquarium
http://reefkeeping.com/issues/2006-09/rhf/index.php
from it (and note the pKas are for seawater, not freshwater):
Figure 2. The structure of inorganic orthophosphate, with a central phosphorus atom (purple) and four oxygen atoms arranged in a tetrahedron. Three of the oxygen atoms can either have an attached proton (green) or be present with a negative charge on the oxygen atom (red). The amount present in each form in seawater varies with pH as indicated.
One bath may be adequate, if you dissolve away the rock surface.
The reason acid works at all is exactly because it forces protonation of phosphoric and carbonic acids. Phosphoric acid does not reform the stronger binding forms (HPO4--and especially PO4---) as long as it is acidic. So you wash that away.
In acids, the rock will be bubbling away, removing the outer surface, as carbonate and bicarbonate are protonated to CO2, which bubbles off.
Additionally, phosphoric acid will not bind to calcium carbonate surfaces because it is mostly or fully protonated. This slide from the scientific literature shows the pH dependence of phosphate binding to aragonite. It does not need to be very acidic to reduce binding substantially:
http://yyy.rsmas.miami.edu/groups/jmc/fla-bay/pp-samples/master1/sld013.htm
The reason acid works at all is exactly because it forces protonation of phosphoric and carbonic acids. Phosphoric acid does not reform the stronger binding forms (HPO4--and especially PO4---) as long as it is acidic. So you wash that away.
In acids, the rock will be bubbling away, removing the outer surface, as carbonate and bicarbonate are protonated to CO2, which bubbles off.
Additionally, phosphoric acid will not bind to calcium carbonate surfaces because it is mostly or fully protonated. This slide from the scientific literature shows the pH dependence of phosphate binding to aragonite. It does not need to be very acidic to reduce binding substantially:
http://yyy.rsmas.miami.edu/groups/jmc/fla-bay/pp-samples/master1/sld013.htm
I don't know if the lanthanum is useful or necessary, but that plan is probably OK. I'm not sure how much lanthanum might bind onto the freshly exposed rock.
Be sure to rinse well to remove loose lanthanum carbonate detritus.
Be sure to rinse well to remove loose lanthanum carbonate detritus.
If there is phosphate or maybe silicate already in the tap water, that's an issue. Otherwise, its not a big concern. I might use tap.
percula99
New member
I read through this entire post and decided to give it a shot. Previously I cooked my first 125 pounds of LR and it took 5 months to get it to where I put it in my DT. I had another 125 pounds and did not want to wait another five months. I put it in a rubbermaid garbage can with a 1/10 bleach/RO water combination for two days. I did two rinses in RO with dechlorinator. I then put it in 100% vinegar. It fizzed like alka seltzer for about 90 minutes and then slowed down. I left it overnight and the next day there was brown foam at the top of the vinegar. I put the rock in RO water with baking soda twice, then again with just RO. I then rinsed it by swishing it around in clean RO in small buckets, changing the water as it got milky. That is four RO rinses so far. It is now sitting on my back deck drying out until the wekend. It smells like the ocean now, no trace of bleach, and only a couple of very pourous rocks have a trace of vinegar smell. I plan on rinsing once more in RO an re-scaping my DT with the previously cooked 125 pounds and letting it all re-seed. Corals will be going in this weekend also and my fish are in QT for a few more weeks as I bought two new ones. I am confident this will work out fine because of all the effort I put in and how the rock does not smell bad anymore. Any thoughts from anyone would be appreciated.
I gave my rock a bleach bath for about 48 hours then rinsed it let it dry rinsed it again untill it no longer smelt like bleach. Today I gave it a 20 min bath in murric acid and it went ok. Some of my rock has some brown on it that seems to be part of the rock, is this rock ok to use? Here is a pic of a small piece with some of the brown on it.
Attachments
Unless the rocks are very cold, I wouldn't bother heating them.
percula99
New member
Randy, I live in Canada and it is still cold here. Tonight it is going down close to freezing. I have my rock drying out on the back deck and seeing as it is dead after the bleach and vinegar I really did not see an issue with leaving it out there. I plan on bringing it in Friday evening to warm up before I re-scape my tank on Saturday. Do you see an issue with this?
No, that sounds fine.
percula99
New member
When I put my cooked LR in the tank (first 125 pounds), about two weeks ago, I have not suffered through any algae outbreaks. I will be putting in my bleached and acid washed rock (2nd 125 pounds) this weekend and completely rescaping the tank. Can I expect an algae outbreak on this rock?
That's what I would recommend yes.
