Upgrade 40gal to 210gal bio cycle?

[whotzler]

So with this upgrade I will be including my current tanks water and bio load a few small fish, assorted crabs, snails, shrimp and 40 or so corals half LPS half SPS and 40lbs of rock. The big question is all about the new dry rock I will need to add around 150-200lbs.

Can I add the new dry rock along with my current 40lbs of live rock with all my corals on them and my current live stock to the new tank, fill it with 40 gal. old water and the rest new water and be good to go without cycling the dry rock first separately? My thought here is if the bio load does not change the current live rock should be able to take care of it. Or am I thinking of this all wrong? Does the water volume have an effect on bio filter? Does the addition of the new dry rock have an effect on bio filter?

 

[cjd]

The only concern that I would have is to how clean the new dry is. I would pressure wash it if you have one or scrub brush with a garden hose to make sure anything dead is gone. I would then rinse with rodi water . Reason being if there is a massive amount of decay on that new rock you could have a problem with the tank having a new cycle . 200 lbs. of dirty rock is asking a lot of your established nitrifying bacteria. If you were doing a smaller upgrade I wouldn't even think twice , I would say just do it! For a move like this depending on the amount of livestock I had , I would set up the new tank with new sand , take my time with the scape with the new rock leaving openings for my old rock to fill, put all new water in it and get it running . Wait 30 days for mother nature to run its course then drain the new tank about half , put my old rock in those spaces I had already planned for ,rearrange where necessary , maybe a few handfuls of my old sand to seed the new, fill the tank with my old tanks water and top off with the new tanks water I took out to put my old rocks in. I have transferred tanks so many times in the 15 years I have been in this hobby . My biggest was going from a 60 to a 150 and if I remember correctly this is how I did it. Maybe someone will chime in that made a big upgrade like this , Im sure people will chime in with using magic chemicals and the such, but I have been in this hobby so long that waiting out a nitrogen cycle has nothing on me!

 

[CarrieB]

I think it depends in whether your dry rock is really clean or whether it contains any dead organic material that would impact the bioload.

If it was me, I'd put the new rock in a big tub with saltwater for a week and test for ammonia, nitrite, nitrate and phosphate. Then you'll know what you are introducing to the tank and whether you might want to cycle/cure the rock first.

 

[whotzler]

So an acid bath to make sure rock is clean, then set in water for week and test. If no sign of ammonia, nitrite or nitrate should be good to go?

I would really like to add all rock new and old at once, it is so much easier to do a good accuascape without water in the tank. But at the end of the day the safety of my live stock has to come first. Of course this brings up another concern as the live rock and corals will be out of water for maybe 30 min to an hour while filling tank?

 

[CarrieB]

The live rock will be fine, not sure about the coral. Can you set up a temporary holding tank for them? Could be a tub.

 

[whotzler]

I can and will for some, but all SPS are encrusted on the rock. Im gonna have to work fast. Iv heard that in the wild tides sometimes expose corals for an extended period of time and they do fine.. I am going to have to do some more research on this before making the plunge.