Problems

[AdamHorton]

Over the past week or so, most of the fish in my tank have died. I have no idea why, since everything I know how to test for has been perfect for a couple of months, and I've done multiple readings recently.

Ammonia: 0
Nitrite: 0
Nitrate: 0
pH: 8.2-8.4
Alkalinity: 4.5 mEq/L
Specific Gravity 1.024-1.026

I have no idea what could be wrong. I called the LFS and they weren't any help. I plan to take a water sample up there to test, but I'm having car trouble and the earliest I can possibly make it up there is tomorrow night. If you want more details if you're trying to diagnose what's wrong, the link in my signature has all of that.

At this point, I'm just wondering what's best for the remaining fish. The only way I can get them into an established tank that I know is good would be to give them back to my LFS, which is a last resort. I've been seeding a small HOB filter for a little over a week now in my refugium, so it is possible for me to put all of my LR aside, and get all the fish into a 20G QT tank with that filter, but I don't know if that will even help. The fish left that have a real chance of making it are 7 damsels and 1 pseudochromis.

I have a feeling the answer is to give all livestock back to the LFS and start completely over from zero, but I want to know if there's any other option for my fish, my LR, or either of the filters I have set up at this point.

One more thing, I'm going to be on vacation starting this Saturday for a week, so anything drastic that I do has to be done before then.