switching tanks again

[ffsteve]

I'm down sizing alittle 180g to a 75g. can i just switch everything from one to the other?

i'm going to do some cool rock work for the new tank and was going to use some of the old and some new water to fill it. I have a 55g barrel i was going to use when i do the rock work(pump out the tank to the barrel, then replace it when i'm done). i think it will take a few days to do the rocks, drilling, glueing, and stuff.

do i still have to let the tank cycle? same sump is going to be used, skimmer, ect,

 

[frank180reef]

I thnk it depends on whether u have new sand and how u treat the rocks .... meaning did all the bacteria live

 

[bossreef]

My tanks are much smaller, but I did this recently with 2 Biocubes and a 27 gal tank. I combined two 14 gal Biocubes into the 27 gallon tank without any problems. It took me much longer than I had originally hoped for. I had to carefully remove everything from one of the Biocubes, to make sure that I didn't crush my pistol shrimp and goby. I kept everything submerged for the duration of the tank consolidation.

I re-used about 2/3rd of my sand and about 60% - 70% of the existing water. The remainder of the water was freshly made. Both of my tank parameters were spot on and have always been stable.

The new tank didn't have any cycle at all, but the water was cloudy for several days. The 27 gal had very weak filtration at the time; an aquaclear HOB was used temporarily.

Just a note: I added about 2 cups of new sand about two weeks later, thinking that such a small amount wouldn't matter, but I was wrong. The new sand created a small diatom bloom that stayed around for about a week.

 

[ffsteve]

I'm switching the sand over too. i'm going to fill the tank with old water from the 180. (about 50gallons) and add 25g of new water. when i do the rock work i'll drain the tank to the 55g barrel, do the work and refill. do that over and over intil i get it the way i want it.

has anyone have rock sticking out of the top of the tank?