So I have some bad news, the flame angel died today. I did a freshwater dip and after it was completed, it died probably no more than a few minutes after being back in the QT. I have zero idea what went wrong, and I'm pretty upset at the moment. Here's what I did.
I put 1 gallon of RO/DI water into a black bucket. To raise the pH, I used API Proper pH 8.2. I have a small scale I use to weight out medication, so I weighed out what the bottle said: 1 scoop for 10 gallons. The scale was 1 scoop was 9.3 g, so for 1 gallon, I would use 930 mg.
I placed the black bucket into another 5 gallon bucket with just tap water inside. The heater was in the tap water so that it would raise the temp in the bucket without actually being in the water. I added the 930 mg powder and stirred with a spoon until all the powder was dissolved. I then ran an airstone for about 2 hours while the water heated up. When the temperature was 78 degrees C (same as what it was in the QT), I tested the pH using an API freshwater kit test and the High pH test. The pH was 8.4. I then tested the pH in the QT, it was between 8.0 and 8.1. Since the pH wasnt an exact match, I added 1 cup of RO/DI water to lower the pH. I then let the water aerate for another hour. After testing the water again, the pH was 8.0 or so I thought from the color of the test.
With the pH appearing to match, and the temp matched, I then caught the flame angel with a net and put it in the water with the airstone going. The fish was in the water for 4 minutes and 30 seconds. It behaved like what I've read, it began to lay on the ground and was breathing, so I moved the airstone around so that it would keep swimming around. Had to do that for most of the time the fish was in the water. At some points it would go limp aside from breathing, but if I moved it a bit with the airstone it would snap out of it and start swimming again. It was hard to see if anything was actually coming off the fish with the airstone going, but I kept at it since I didnt want the fish to suffocate.
When the time was up, I caught the fish with the net and put it back in the QT. It started to swim around a bit and breathe normally. It then swam into its tubes and stayed there for a while. After about 20 minutes I checked on it again and realized it wasnt moving. I got it out of the tube and it was completely motionless.
What ****es me off is I looked in the black bucket, I didnt really see anything. There was dust and maybe some bits from the net, but I couldn't really see any type of bug or parasite. So the fish died for nothing.
Now, I have done a FW dip before, on a clownfish, I did something similar to the above and the fish survived. So what could have possibly happened here? Say the pH was off somehow. At most the pH variation was a jump from 8.0 in the QT, to 8.4 in the dip (thats assuming that my final pH test was off and the value was from the first test). Would a difference of 0.4 or 0.6 pH units lead to death in a fish? Especially after people here were saying not to even worry about the pH difference? Is it possible that the alkalinity was off or something? I didnt test the Alk in either the QT water or FW.