how much to remove at one time??

[paullisa51708]

most of the rock in my 90 gl is lava rock and i think its ugly and also have heard that it can cause problems so im going to start taking it out over half of all the rock in there is lava rock so i dont think i can take it all out at once as it will shock the tank yes no? im going to go really simple and make some stacks of rock real simple is starting to look great as ive seen alot of reef scapes that blow me away
any input please

[jenglish]

Well, I never recommend removing more than 1/3 of bioballs at one time if that is the media for biofiltration being used. I think the same rate of 1/3 a week would still be about as quick as I wanted to try it. Of course if you had a very heavily stocked tank even that may be too fast.

[paullisa51708]

3 clowns a blue hippo a royal gramma an algae blenny
condalactic anenome 2 sps corals

[sedor]

Its always better to move slower, so although I don't think removing the rock all at once would hurt the system, why risk it...just remove 1/3 at a time. Only issue that might arise is the detrius that is kicked up from moving the rock work around and the loss of bacteria culture, but that will build back up quickly. Its more important to add the new rock slowly...and if you purchase it uncured make sure you cure it first. What I would probably do is replace the lava rock with new dry base rock and just let your current LR convert it.

[jenglish]

I don't think adding rock that is fully cured and cycled needs to be spaced out. To me that would be no different than switching rock between different tanks. But this is only if the rock is cured and cycled. Obviously putting rock of unknown quality into a tank can cause a mini cycle.

[paullisa51708]

whats the bad thing with lava rock other than its ugly does it release anyting into the tank