Need help for fin/tail rot, quick!

[sangenuer]

I'm going out of town later today and am taking my crowntail betta to a friend for "fishsitting" while I'm gone. I need to figure out what to do before we leave.

The fish is in a 2 gallon (I think) aquarium with a filter and light. I have one small live plant and one betta in the tank--we've had the fish about three months. I don't have a heater but I do have a thermometer; the water is generally between 78 and 83 degrees. I've been having some problems with algae lately. I confess, I let the tank go too long without water changes a few times over the past several weeks (although the algae problem has been persistent even with weekly partial water changes). I have the light on a timer, about 4 hours in the morning and 4 or 5 hours in the evening. The tank is not in direct sunlight.

Three days ago I did a big water change, probably 60%. I scrubbed the algae from the tank sides with a new algae scrubber and added a couple of drops of Tetra Algae Control with the new water. I left the filter out for a few hours.

Yesterday I thought it seemed like the fish's fins were shorter than they used to be, but I wasn't sure. This morning I happened to see a picture from when we first got the fish, and they definitely are. There's a tiny bit of whiteness around the edges of some of the fins. I honestly don't know if this started before or after I put the anti-algae chemical in.

Last night I checked ammonia and nitrates. Ammonia was at zero, nitrates between 0 and 5ppm. I don't have any other test kits.

I just did another big water change to try to get rid of the chemical, in case that's what is causing this. I won't use it again. But now I need to figure out what to do and what to tell my friend to do to help the fish get better. Here are fish medications/treatments that I happen to have in the house (and I don't think I'll have time to get to the store before we leave):
Melafix
Maracyn-Two
API Fungus Cure
Stress Zyme

Should I use any of these? Whatever I do, I'm going to need to tell my friend to continue while I'm gone. Help!

Lisa

[sangenuer]

Here are some pictures in case that will help:


Spike, when he was new



Spike, today

[sangenuer]

I had to take the fish to my friend, so here's what I did when I got there:

Added stress zyme to the water
Started a course of Melafix (1/4 tsp per day, told her to continue for 7 days then do 25% water change)

I asked her to do the 25% water change in a week or so, then add Stress Zyme again with the fresh water.

I took the filter out of the tank since the Melafix said to remove activated charcoal. So now the filter pump isn't running at all. Is that okay? Or should I tell her to put the filter back in? It's an all-in-one filter, with charcoal built into it. I could also tell her to turn the filter pump back on so the bio wheel still runs, but it creates a fairly strong current when there's no filter in it.

Please let me know if I need to tell her to do anything differently. I can still take the other medicine over to her before we leave if I need to.

Thanks,
Lisa