switching tanks

[davejnz]

My current 30 gal is stocked with SPS frags and a 1.5" SB,it has one of those crappy HOB overflows that i'm always having top mess with.The glass is also scratched up too,sucks for taking pics so i figured its time for a new tank.
I'm building a new stand for my new 30gal.It will have enough room to accommodate my old 30 underneath it to use as a sump(temp refuge).I had it drilled and installed an internal overflow.This system will have just enough sand to cover the bottom glass
So,what would be the best way to do the switch?All ideas are welcome.

[Reptoreef]

Ummm... keep your 1st 30 as is only where it will act as the sump... run things like that for about a month or so(new tank and starter stuff in 30 on top)... then gradually add the fish, inverts(other than corals), and finally, the corals... softies to stonies slowly with the lighting already in place. The problem I can imagine is lack of room for the existing lighting that is already on the existing 30 as a refugium light. Reguardless, with a new addition, there is going to be a cycling that occurs.

[davejnz]

yeah,thats what i was worrying about(cycling).I was hoping to just add all current tank water to new one,minus the sand.Then,add LR but keep frags in a temp holding tank.Use my current sump while the newly stocked 30 goes thru its mini-cycle(hopefully not too long because the LR will only be out of water minutes and no old live sand).Then do daily waterchanges while siphining detritus off of barebottom tank.After a few days,add a 1/4" of LS and then start adding SPS back in.That will give me time to design/install baffles/drill for float valve, in old 30gal to make it a bad a** sump.

[dakar]

Yup, definately going to be a cycle, tried the same thing with a 10G tank I set up as a hosp tank (used CC instead of sand), just pulled 10 gals off the main tank and added to the HT, got a MAJOR cycle, nitrates went off the chart.

[jerryc]

I changed from my 29 to the 55 by siting it up withe sand and about 80% full of water
with about 25 pounds live rock let run for 6 weeks toke out some water
moved everything over including all the water from the 29.
All seamed to work out great,GOOD LUCK

[davejnz]

thanks for sharing your experience Jerry,I think i might do something similiar.My only problem is i want to set up the new 30/stand where the old one sits.When i fill it up,it might be a PITA to move