maracyn, Maracyn-Two and UV sterilization

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Aquarium Advice Regular
Jul 27, 2007
I purchased a few fish last week and one died the next day. Today it seems that a few of my fish just aren't quite right. I have purchased Maracyn and Maracyn Two to use in the tank. My question is: Can I use the UV Sterilizer while medicating the tank?
All water parameters are great. Tested for ammonia, nitrate, nitrate, phosphate, Ph.
40 gal, freshwater, 3.5 wpg CF lighting, heavily planted tank.

No signs of parasites (ich) but there is some flashing against the rocks by a few fish.
That will teach me that I can too afford a QT!
As far as I know, you should NOT run the UV sterilizer during medication with antibiotics. It pretty much makes them useless.

That said, maracyn and maracyn two are antibiotics, and if your fish are flashing and rubbing, they probably have a parasite issue and not a bacterial issue. Might not hurt to forgo the meds for now and try the heat treatment (raising temps to, and KEEPING THEM STABLE at 87F atleast) for around 2 weeks.

HTH. :)
Thank-you and yes it helps.
As soon as I noticed that there was flashing I turned up the heat and plugged in the UV. Yesterday I noticed my angle's back fins were a bit ragged. I felt I had better use meds just in case.
I will turn off the UV for now and try to treat for the Angel's issue. I was hoping I could try to help everyone at once.
I would monitor the fish closely. Medicating without a clear indication of what you are treating is a bad idea. I would also be looking at increased surface aggitation if you are keeping the temp high. Frequent water changes might be in order to help the angel's fins repair themselves.
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