How to clean rock for a new tank?

[TakenAuthority]

Hi guys,

 

A friend of mine is shutting down his large tank and retiring from the hobby after a ich breakout killed all of his fish. He's offered me the rock (Caribsea life rock) for free, roughly 35kg.

 

I'm looking at starting a large tank at some point soon but obviously want to totally purge and nuke the rocks so they're as safe and clean as can be. What's the best way to go about this?

 

I don't care about killing the good bacteria on the rock. Having been in a tank with ich (and who knows what else) I want to give myself a good chance by purging and nuking the rock the best way possible.

Obviously the safest thing to do would be to just buy new rock but since I'm being given a hefty amount for free, which is a massive saving, I'd like to at least try clean it up.

 

Fish only system so no Zoa's or anything should be present. My friends tank never housed coral.

 

What's the best way to do this?

[rough eye]

if there is any value, the value in the rock is that it's not clean. i wouldn't do anything to it. if you're starting a tank wait a couple months before adding any fish (which you should do anyway while letting the cycle get started) and there will be no ick to worry about.

[seabass]

^Agreed, mature live rock usually gets you so much further in this hobby than clean dead rock.  Unless it's covered with pests, just keep the tank fallow for eight weeks and it'll be free of ich.

 

I wouldn't be afraid of some green hair algae either; and aiptasia can be dealt with too.  There are curable problems which don't warrant killing the rock, and others that might justify starting over.

 

If the rock is without redemption.  You could hose it off; then put it in a bleach solution to dissolve the organics.  Then hose it off again, and soak it in freshwater with Seachem Prime to help dechlorinate it.  Rinse it out one more time, and let it dry.

 

Finally, you'll want to rebuild the biofilter on the dead rock.  Fill your tank with saltwater and add a bottled nitrifying bacteria culture to seed the rock.  Then:

• Use DrTim's Ammonium Chloride to raise the ammonia level to 2 ppm
• Wait for the ammonia level to drop to 0.25 ppm
• Repeat until your tank can process 2 ppm of ammonia down to 0.25 ppm within 24 hours

Then do a water change to bring the nitrate level down within your target range (usually less than 10 ppm).

[Clown79]

Set the tank up, Keep the tank fishless with the rock in it for 8- 10 weeks and its ich free.

 

Nuking the rocks,  why? Good established rock is sought after because of all the beneficial life in it. 

[Superdave]

As said above, bleach is good way to nuke.  Drying completely out in the sun for a few weeks (even a few days really) will do the same thing.  

 

Just me, but I would go the dry rock and let the bio-cultures establish over time.  You could always set yours up (with the dry/nuked rock) then add a piece or two of good live rock from a LFS or even a cup of live sand from someone's tank to "seed" it with cultures.  That way you have zero worry.  

 

What has been said above about going fishless and letting it be should work fine as well.  

 

Good luck!

[seabass]

8 minutes ago, Superdave said:

Drying completely out in the sun for a few weeks (even a few days really) will do the same thing.

Bleach helps dissolve the organics.  However, simply drying the rock will leave the organics in place and cause an ammonia and nutrient spike.

[Superdave]

2 minutes ago, seabass said:

Bleach helps dissolve the organics.  However, simply drying the rock will leave the organics in place and cause an ammonia and nutrient spike.

Hmm, maybe a week would be a bit brief but in my experience a few weeks out in the sun there isn't going to be much of anything to create a spike.  (if need be, we can meet out in the parking lot you old-school-Nano-Reefer and fight about it..! 🙂 )  

 

seabass isn't wrong about bleach being best way to nuke it.  

[seabass]

20 minutes ago, Superdave said:

Hmm, maybe a week would be a bit brief but in my experience a few weeks out in the sun there isn't going to be much of anything to create a spike.  (if need be, we can meet out in the parking lot you old-school-Nano-Reefer and fight about it..! 🙂 ) 

 

The reason I brought it up was that back in 2013, I took a bunch of dry rock and pressure washed it to help remove any organics (even though no organic matter was apparent).  Then I soaked the rock in a bucket for six days, which resulted in more than 2.0 ppm of ammonia and 0.23 ppm of phosphate according to a Hanna Checker.

 

It was a surprise to me.  But now I don't trust dry rock unless I cure it first.

[Superdave]

24 minutes ago, seabass said:

 

The reason I brought it up was that back in 2013, I took a bunch of dry rock and pressure washed it to help remove any organics (even though no organic matter was apparent).  Then I soaked the rock in a bucket for six days, which resulted in more than 2.0 ppm of ammonia and 0.23 ppm of phosphate according to a Hanna Checker.

 

It was a surprise to me.  But now I don't trust dry rock unless I cure it first.

Hey, this hobby is all about personal experience as it is true evidence/data of something we learned!

[rough eye]

if you don't dry the rock, let the tank sit without fish for 2 months.

if you dry the rock, let the tank sit without fish for 3 months. 

 

everybody i read about who only cycled their tank for a week or two has tons of problems.

[TakenAuthority]

Thanks for the replies everyone.

 

To justify why I considered nuking it rather than accepting beneficial bacteria was simply because I'm being overly cautious. In any case, I'd rather start from the bottom and work back up with it since I didn't have to pay for any of the rock vs. getting it into a tank and leaving it fallow as that would be a test of how patient can I be!

 

I'll consider my options as and when my larger tank is delivered 🙂

[seabass]

1 hour ago, TakenAuthority said:

simply because I'm being overly cautious

If that's the case, I'd definitely try to keep it live.  The beneficial fauna is a lot more than just nitrifying bacteria.  Many people quit the hobby before getting their rock mature.

 

However, if I were to dry it all out, I'd probably take the time to build a kick ass aquascape with some aquascaping mortar.

[blasterman]

Just soak the rock in freshwater for a week. Salt water parasites can't survive in freshwater.

 

This will also preserve much of the bacteria.

[Clown79]

18 hours ago, TakenAuthority said:

Thanks for the replies everyone.

 

To justify why I considered nuking it rather than accepting beneficial bacteria was simply because I'm being overly cautious. In any case, I'd rather start from the bottom and work back up with it since I didn't have to pay for any of the rock vs. getting it into a tank and leaving it fallow as that would be a test of how patient can I be!

 

I'll consider my options as and when my larger tank is delivered 🙂

This hobby is all about patience. 

 

Going fallow or nuking the rocks, both will require patience.

 

With nuking the rocks not only do you need to cycle the tank(4 - 6 weeks average)  but you will be waiting a long time to develope all the beneficial life you killed.

 

People pay a lot for live rock for all that life which gives a much better biodiversity and stability to the system than dry rock

 

Or wait 8 weeks going fishless (you should honestly qt any fish you get which could be in qt while you wait out the 8 weeks)

 

Either way equals waiting and patience