Teena said:
I added Melafix yesterday, but they seem to be even worse today. Do you think I should add it again today? I am scared to change too much if they are in shock. I am so confused. Could the severity have to do with their age?
I'd keep the lights of the tank off - that'll help them rest. I'd do a daily 10-15% water change and I would not believe the LFS's water tests - their ideas of "fine" are often way off. I'd like to know the
precise figures for ammonia, nitrite, nitrate and pH and I strongly suggest you get some test kits (try online for better bargains).
Since you replaced the gravel I'm concerned your tank has done a mini-cycle (check my sig for further info if you are unfamiliar with the term). I suggest you proceed with that assumption until you know for sure that's not it.
As your fish are not eating, try to tempt them with some defrosted frozen bloodworm, or some live daphnia or brine shrimp. Keep doing the Melafix (don't forget to remove any carbon from your filter). If they start showing the symptoms of something more serious you will need to use stronger medication, but you can't just shoot in the dark for fear of making things worse.
As you shook up the old gravel it is possible you released "dead spots" of sulphur dioxide, which can poison fish.
I'm not at all convinced by this "shock" diagnosis - it sounds far too flip and far too unlikely. However, they could mean pH shock. Have you had a radical change in pH since changing the gravel? Very often the mulm in old gravel will drop the pH and suddenly being in water with a higher pH could give them pH shock. If that is the case, try doing some water changes with RO water to drop the pH a little (don't be tempted to use chemicals).
