Flukes?

[Consteve]

I have a 37 gallon tank that recently seems to have started having problems.  Three days ago I had a guppy pass, and the next day I noticed a different female guppy was constipated and she passed the next day.  I checked water conditions after both and Ammonia and Nitrite were at 0 ppm with Nitrate at 5 ppm.  Today I have noticed a third guppy, a neon tetra, and a corydora all started flashing after eating this evening and appear to be breathing heavier then normal.  There is a slight pink tint to the guppies gills.  Does this sound like gill flukes or is there some other problem that could be causing the issue?

I appreciate any help! 

[Colu]

Any listlessness hanging near the surface reduced feeding response fish separating from the group and hanging around on there own colour loss also can you try and take a picture of the fish also how long have you had the fish and have you added any new fish recently that could have bought parasites @Constevein to your tank 

[Consteve]

No new fish added to the tank recently.  Fish still go into their normal feeding frenzy.  No further loses just the heavy breathing and that bit of flashing I noticed after feeding before.

[Colu]

On 7/23/2023 at 7:05 PM, Consteve said:

No new fish added to the tank recently.  Fish still go into their normal feeding frenzy.  No further loses just the heavy breathing and that bit of flashing I noticed after feeding before.

What I would do is add an extra air stone and a small amount of aquarium salt 1 table spoon for 10 gallons that will aid Gill function and add essential electrolytes if after a couple of days your still seeing rapid breathing and flashing then I would treat with prazipro do 3 full courses of treatment with prazipro