advice on replacing tank

[johara]

It's time to re-do the living room floors which requires moving my 6 year old 155 bowfront mixed reef with dsb. The rock in the tank ranges from 6 to 20 years old as much of it came from my original tank set up in 1989. My phosphates (per Salifert) range from .03-0.5 depending on how diligent I am with phosphate removers. 7 months of vodka have gotten NO3 to 0, but no change in phosphates.

I am considering replacing the 155 which is at least 10 years old (I bought it used) and has some scratches on the front glass that really annoy me. I would probably go with a 180 rimless if I can find one for a reasonable price.

My questions are:
1) Would you use the rock or take this opportunity to replace it in case they are phosphate reservoirs? I am looking for a more open look anyway.

2) If I ditch the dsb (too old to move safely I think and also likely a PO4 reservoir), and start with new rock, will I kill my fish/corals with a new cycle? What can I do to avoid this?

3) I am strongly considering going T5 as I have been impressed with the SPS coloration I see in these tanks. It would also be nice to forego the chiller the halides have required - expensive to run and noisy. What fixtures do people recommend for a 180? Are 60" bulbs sufficient for a 72" tank?

Attached is a not too out of date photo of the tank.

[flying_dutchman]

You may want to look into "cooking" your rock, this will remove phosphates and shouldn't cause a cycle or at least a very little one. There are a lot of threads about this and I'll see if I can find one.

EDIT:
Here you go:
http://www.reefcentral.com/forums/sh...hreadid=437342