tank is crashing!!!

[hawaiiguy]

I don't think anyone down here in Lethbridge has salifert. The test kits I have are hagen. There are only two pet stores that deal with salt water stuff here and they both carry hagen. Anyways, I will pick up a PO4 kit and an alk kit later today. I already have an ammonia kit, nitrate kit and pH kit. Do I need anything else?

Mobydick, yes I did change things around in the tank about two weeks ago. I decided to try and find a goby that disappeared in the rocks. I took the rock work apart and then put it back together. That was it. It made the water pretty dirty but I did a massive water change and things looked normal soon after. Do you think that could've caused all my problems?

Other than the rock rearranging, everything else has stayed the same (lighting, Ca dosing, salt, etc).