Ocean Rock

[jcolley]

the ocean rock in our tank it going very green over time, is there anything we can do to get rid of this or is it naturally okay for it to change colour like this?

Thanks

phil & jo

[Gillybaby]

The green is most probably an algae of some sort. An increase in clean-up crew and lowering of phosphates/nitrates may help.

If I were you though, I'd start removing the ocean rock and replace it with live rock. You can do this a piece at a time to spread the cost if there is a lot. Much better for your system and displaces a lot less water too.

[Reefer]

The ocean rock I had in my old tank took on a green tinge over time and is probably what Gillybaby says, Algae of some sort. I dont beleive clean up crew will shift it though as I always had a good stock of clean up crew in and it always looked greenish.

[Tangman]

Hi Phil & Jo. As said by Gilly i would dump the ocean rock as it does not do anything towards filtering your tank, and replace with some good Live Rock and make that it is loosly aquascaped so that the water can flow through it. Also make sure you have plenty of flow in your tank ie 20 to 30 times the volume of the amount of water in the tank. HTH. Eric

[Kev]

Another point that I always think of, not forgetting the filtration benefit of live rock over ocean rock, but live rock, in my opinion, looks far nicer and more natural to the eye in the aquarium setting.

[Pinkfish]

Sorry if this doesnt go down well with you guys but I dissagree about the claims you make about ocean rock.

Live rock if I am not is extreamly porous and covered in all sorts of biological creatures and organisms, with coraline algae growing all over it.

If you get good porous ocean rock then there is no reason why it will not become live rock over time. As all the organisms from the live rock will spread into the ocean rock. You all may disagree but I have Ocean rock in my tank as well as like rock, and the ocean rock now has coraline algae growing on it.

I agree that at the beginning ocean rock doesnt do anything for the filtration of the tank, but after a while it WILL get colonised by organisms and become live rock.

Adding ocean rock to your tank at the beginning will not cause any harm.
The fact that you say you have algae growing on the ocean rock proves that it does get colonised. Even if the green algae isnt what you want.
Good Circulation and Keeping Phos down is the key. I have started to use ROWAphos in my sump to eliminate Phos.

I have found many DIY articles on making your own live rock on the fabulous internet.

Mike

[Gillybaby]

Hi Mike, don't worry about disagreeing, that's what forums like this are all about...discussion.

However, I have always understood that the "live" part of liverock has nothing to do with what grows on the outside but has everything to do with the bacteria that colonize the inside of the rock. Hence the need for good quality liverock to be porus which makes it much better for filtration.

Ocean rock by its very nature is dense and is a lot heavier than liverock. This does not provide a good home for the necessary bacteria and hence cannot become as live as liverock, no matter what coralline and other algaes grow on the outside. If your ocean rock feels about the same weight as your liverock then there is a good chance that either your ocean rock is dried out liverock (which is good) or your liverock is ocean rock with stuff growing on it (which is not so good).

The homemade liverock works so well because it replicates the porus nature of liverock found on the reefs, providing a perfect place for the bacteria to thrive.

[Kev]

Hi Mike

No problems with disagreement. If we all agreed we would never move forward.:)

However, in my opinion, Ocean Rock will NEVER be as effective as quality live rock as a tool to filter the water in a marine system. Ocean rock, in my opinion, does not have the same porosity as live rock. It is indeed all of those hollow area's within the live rock where anerobic conditions occur, effectively allowing conditions in which bacteria can flourish which remove nitrates from the water very effectively. This same effect can not be as efficient in ocean rock, it is simply not as porous. Check the weight of ocean rock against live rock, that gives an indication of the porosity of the live rock compared with ocean rock.

It is imaterial whether or not ocean rock will be colonised by algae. Any surface in an aquarium will be colonised by algae, bacteria, and all sorts of organisms. But this will never give ocean rock the same quality as live rock. Believe me, if it did, a lot of aquarists would not waste their hard earned brass on live rock. But, the experience of many proves what works best!:D

Kev

[Gillybaby]

lol Kev, so are we great minds or fools?

:D

[Kev]

Probably fools!:D

Mind you, something is going pretty well with our reef tanks!!!!

Kev

[Tangman]

H Mike aka Pinkfish i am with Gilly and Kev on this one, there is no substitute for good live rock and IMO Ocean Rock will never become live and work as well as live rock. HTH. Eric

[Reefer]

Ocean Rock is the wrong sort of rock to hope to turn to live rock. Even if it was porous enough it would take a couple of years to become anywhere near as effective as your bought stuff. I read an article about man made live rock, that gets left in the sea for 5 years to 'seed' properly.

Pinkfish what is this Rowaphos you have discovered? I've never heard of it?? Have you Kev?! Must be a new product on the market?

[SteveS]

sigh

mike, ocean rock is imo is a waste of space, it will not turn into live rock, did your lfs who stole your money with false info and fish sales not advise you of this??

steve

[Kev]

I have found many DIY articles on making your own live rock on the fabulous internet. Mike

Hi Mike

This info has been around for years, however, there is a wealth of difference between this "home made" live rock and inert Ocean Rock.

Kev