Use of antibacterials in a tank that isn't fully cycled yet?

[hydra70]

Looking for any input here, please.....

I've been a semi-regular over in the "Getting Started" area, set up a tank, didn't have it cycled, put in the fish.....and then went to school with much help.

Some background:
I have two spiny eels (three-spots) in this 20 gal tank @ 78F. I've lost two others already, and don't want to lose any more. The prevous two were healthy visually/behaviorially for two/three weeks, but then started showing light colored/greyish patches, roughly 1/4 inch across. Usually only one of these spots on the whole eel. The first one died within 3 days of first sighting. My AA forum assists suggested that it sounded like fungus, I tried some anti-fungals, didn't work. Second eel died the same way, about a week later, but this time the anti-fungals went in sooner.

Now another one is exhibiting a lightish patch on one side, an inch or two aft of the gills, and I don't want to lose him/her. If anti-fungal meds didn't work for the other two, I don't see any reason to waste my time with them now, right? But here's the catch: I'm nearly cycled on this tank - finally.

Latest water test (12 hours since most recent 40% water change):
ammonia: 0.75ppm
nitirite: 1.0 ppm
nitrate: 15 ppm

I've been told that I am finally within a week or two of everything coming into balance - after 6 weeks of twice daily water changes....... - and I don't want to set that back, if I don't have to.

Now here's the question:
If the anti-fungals can't help my eels, is it reasonable to try some anti-bacterials? Like Melafix, for example? Can they potentially help my eels? Are they going to wreck my cycle progression?

Any suggestions very much appreciated.

 

[Devilishturtles]

You might have run into some issues using certain meds on scaleless fish. I don't know what you used, but did you read beforehand to see if there are any warnings about treating scaleless fish?

Can you get a picture of what you are talking about? I can't really imagine anything that looks like that. If I had to guess, I'd say some sort of columnaris and an antibacterial med would work. Start off with something like tetracycline (read the package re: scaless fish first) as it has been less known to mess with water chemistry.

HTH