If you are unsure of how to do a water change then it is probably best to leave everything alone

Thanks Marie, I wasn't sure how complicated it was and was worried to try. I appreciate it. I'll keep trying the vinegar for the pH. I think another fish might be missing, but I guess there's not much I can do about that now.

Thanks again all!

-L.

What is the PH now?
How much vinegar have you added?

The pH is back up at 8.8 - I've added 4 tsp of vinegar so far and I took the tube out of the dosing pump for alkalinity

if you have a 120 gal tank, you will need to add about 20 tsp of vinegar to lower the PH by 0.3, keep adding the vinegar until you have added 20 tsp then see what the PH is.
is the water still cloudy?

OK, I've added 7 tsp now - the pH is at 8.71.

How long should I wait between teaspoons?

The water is less cloudy, but still more cloudy than usual (probably because it hasn't had a water change in a week).

if you are adding it to a high flow area in the sump I would wait about 10 seconds, if adding to the tank wait 30sec

do you have a salinity meter? ifso, check the tanks salinity

i'm in ontario so i'm getting ready for bed. lower the ph slowly, 0.3 at a time then wait an hour before lowering more, try to get it to 8.3, google water change on a marine tank, there will be lots of videos, a 20% water change would be very helpful. good luck

is there nobody in the calgary area that can run over and help out with a water change?

I wish I was there to help you man.