mysterious green fog

Question
I have a 10 gal. with a few guppies.  Two have died. One has remained sick with multiple symptoms. As instructed by my fish store expert, I am treating with Maracyn & Maracyn-Two. The instructions with the medicine say it's o.k. to use both. I treated last night.  The water has been green tinted and a tad cloudy due to the meds.  This afternoon the water looked as if the water flowing from the filter was a green a fog.  I checked the ammonia, nitrates, ph, etc. and all is perfect.  I thought maybe the meds were building up so I put the carbon filter in to alleviate the fog and did a 30% water change.  This evening it's worse than before the filter and water change.  It's as if the "green fog" is growing.  Now the fish are all at the top of the water gasping for air.  The chemicals still all check out perfect.  The water doesn't smell or anything.  I'm stumped but I'm afraid I'm going to lose the whole tank if I don't do something. Please advise.  Thanks for your help.

Answer
Hi Anthony,
The gasping at the top is a very serious sign something is terribly wrong with the water.

Its very strange I do not recall Maracyn and Maracyn-two causing such a drastic effect when I've used it before. With your fishes symptoms, is it possible for you to just use one medication for now? Just to give the fish a break.

I would do a 50% water change every day or perhaps twice in one day to help the fish out.

I like to, whenever having to dose the aquarium--- to do a daily 50% water change and simply re-dose the med after the change. This is against medication instruction but it does no harm and is actually better for the fish. Most medications loose their effectiveness after so many hours in the tank and pollution is going to build up quick so doing a good-sized water change before re-dosing just makes sense.

I hope this helps and all goes well!
Karen~