upgrading tank questions

JDVC · 07-30-2002, 01:30 PM

Bought myself a pre-drilled 125 for my birthday a few weeks ago, and have a few questions about the upgrade process. So here we go..

My current tank is a 40gal, little over a year old. I want to use this as the sump for the new tank. I will be using southdown sand this time (will seed with the sand from the 40gal) and getting about 100lbs more live rock from premium aquatics. Can I switch the entire tank over in one day? Or will the new tank need to cycle first with the addition of new sand/rock?

If yes on the cycle, then here's the next question. With my current tank becoming the sump, I can't switch my skimmer over until I take that tank down. Will having no skimmer be a problem during the new tank cycle? I will obviously have circulation in the tank, just no skimming.

Thanks much-
John

CherubAngel · 07-30-2002, 02:15 PM

I just recently upgraded myself. I cycled my larger tank frist. When you add any new live rock, even if it's cured, there are still some critters that are or will be dying off. There is way too much new water in a 125 g for your fish to be stable. My tank has been set up for 8 weeks, my water chemistry is perfect, everything is beautiful but I am terrified to add my babies!
I would definitely cycle to tank first, and then even be cautious. I have not added my skimmer yet, and my tank cycled fairly quickly. I would not rush things. I am only upgrading from 35 hex to 75 g but I do not plan on adding fish for at least another two months or so.
Good Luck,
Jill D.