puter
Active member
Tell anyone outside of the hobby that you spent several hundred dollars to buy "live rocks," covered with dead and dying organisms, for your fish tank and they'll look at you like you're crazy... or stupid.
Tell them that you're going to pitch several hundred dollars worth of "live rocks," or worse, get out of the hobby, because your live rocks are covered with life... just the wrong kind --bryopsis, caulerpa, cyano algae, aiptasia and majano anemones-- and you'll remove all doubt.
Yet, it happens all the time. These aquarium pests are amazingly resiliant, and once they've gained a foothold, attempts to control or eradicate them can be exhausting and/or futile.
When the traditional methods of control have failed, or you're dealing with old rocks, rocks covered with pests, or rocks that may have been exposed to medicines/substances that may be harmful to reef tank inhabitants, it may be time to consider a more drastic approach: rock reincarnation.
Rock reincarnation differs significantly from "cooking" rocks. Cooking rocks typically refers to depriving the rocks of light for an extended period of time, in the hope that all the light dependant pest organisms will die off but the beneficial bacteria and coraline algae will survive. This can take a long time to be effective and carries the risk that pest organisms will not be wholly eradicated. Majano anemones, for example, can survive months without light. Just a few surviving organisms may result in reinfestation.
Rock reincarnation, on the other hand, refers to killing everything on the rock, disolving away the outer layers of the rock to remove impurities, and then reseeding the rock with bacteria and coraline algae to bring it "back to life." Thoroughly cleaning the rocks, thereby making them "dead", only takes a couple days. Making them "live" again, by reseeding and giving the bacterial populations and coraline algae time to regrow, takes many months.
If you've got the time and want to ensure your rock is pest free, here's how you can reincarnate your rock:
1) Bleach the rocks.
Bleaching the rocks will kill everything on them and help disolve organic material. Rinse the rocks off by repeatedly dunking them in a bucket of water. Then, put them in a container of water (tap water is fine) with a small powerhead to keep the solution circulating and add enough bleach so there's a 1:10 (or stronger) ratio of bleach to water.
Wait 24 hours or so, pull the rocks, and dunk/swish them around in a bucket of RO water, rinsing them well. Your rocks will be significantly whiter. Some will have rust and/or gray discoloration. You may find some collegen-like substances left over which typically are easily removed (see the picture of the pump).
After the bleaching step your container may look like this:
Be sure to thoroughly wash it before continuing since bleach and muriatic acid can react and produce a deadly gas.
2) Muriatic Acid Bath.
Muriatic acid is nasty stuff that can easily cause significant and permanent injuries. Use appropriate **SAFETY PRECAUTIONS including eye protection, adequate ventilation and acid-resistant gloves** when working with or near the acid. I strongly recommend that you don't use it indoors. Make sure kids and pets can't get anywhere near where you're using it.
20 minutes later:
More acid:
Acid bath at 3 hours:
Tell them that you're going to pitch several hundred dollars worth of "live rocks," or worse, get out of the hobby, because your live rocks are covered with life... just the wrong kind --bryopsis, caulerpa, cyano algae, aiptasia and majano anemones-- and you'll remove all doubt.
Yet, it happens all the time. These aquarium pests are amazingly resiliant, and once they've gained a foothold, attempts to control or eradicate them can be exhausting and/or futile.
When the traditional methods of control have failed, or you're dealing with old rocks, rocks covered with pests, or rocks that may have been exposed to medicines/substances that may be harmful to reef tank inhabitants, it may be time to consider a more drastic approach: rock reincarnation.
Rock reincarnation differs significantly from "cooking" rocks. Cooking rocks typically refers to depriving the rocks of light for an extended period of time, in the hope that all the light dependant pest organisms will die off but the beneficial bacteria and coraline algae will survive. This can take a long time to be effective and carries the risk that pest organisms will not be wholly eradicated. Majano anemones, for example, can survive months without light. Just a few surviving organisms may result in reinfestation.
Rock reincarnation, on the other hand, refers to killing everything on the rock, disolving away the outer layers of the rock to remove impurities, and then reseeding the rock with bacteria and coraline algae to bring it "back to life." Thoroughly cleaning the rocks, thereby making them "dead", only takes a couple days. Making them "live" again, by reseeding and giving the bacterial populations and coraline algae time to regrow, takes many months.
If you've got the time and want to ensure your rock is pest free, here's how you can reincarnate your rock:
1) Bleach the rocks.
Bleaching the rocks will kill everything on them and help disolve organic material. Rinse the rocks off by repeatedly dunking them in a bucket of water. Then, put them in a container of water (tap water is fine) with a small powerhead to keep the solution circulating and add enough bleach so there's a 1:10 (or stronger) ratio of bleach to water.
Wait 24 hours or so, pull the rocks, and dunk/swish them around in a bucket of RO water, rinsing them well. Your rocks will be significantly whiter. Some will have rust and/or gray discoloration. You may find some collegen-like substances left over which typically are easily removed (see the picture of the pump).
After the bleaching step your container may look like this:
Be sure to thoroughly wash it before continuing since bleach and muriatic acid can react and produce a deadly gas.
2) Muriatic Acid Bath.
Muriatic acid is nasty stuff that can easily cause significant and permanent injuries. Use appropriate **SAFETY PRECAUTIONS including eye protection, adequate ventilation and acid-resistant gloves** when working with or near the acid. I strongly recommend that you don't use it indoors. Make sure kids and pets can't get anywhere near where you're using it.
- Use RO/DI water
- Fill clean container with rocks, RO water, small powerhead.
- Slowly add muriatic acid (careful, it will bubble vigorously. Keep your face away and don't breathe the fumes.) **Always add acid to water**
- When bubbling decreases, add more acid. (I typically end up using a 1:10 ratio of acid to water. The acid bath won't take more than a few hours)
20 minutes later:
More acid:
Acid bath at 3 hours:
- When finished, add plenty of baking soda to deactivate any remaining acid.
- Rinse rock well with RO/DI water
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