I've Lost 5 Fish And A Frog :(

[pirategrl]

My tank has been running for a year. I do 25% water changes every other week. I tested my water and everything looked good. ammonia 0 nitrites 0 and nitrates >5. Since I'm still new at this I also took my water to be tested at the pet store and they said everything was in normal range. I didn't get any numbers. I don't know what to do. It looks like the fish are kind of red looking around their gills... Could this be a parasite or bacteria? I have lost 2 neons, 3 german rams and an African dwarf frog. I had my rams over a year now... I'm devastated and worried about the rest of my stock.

It's a planted tank with lots of driftwood. 55 gallon

We have left_
1 bristlenose pleco
6 neons
1 german blue ram
2 dwarf gourami
1 African dwarf frog
2 siamese algae eaters
8 corydoras
6 kuhli loach
1 fan shrimp
Every thing I read points to ammonia but my ammonia is testing fine....

 

[WILDER]

What the make of the test kit you are using please?
 
Do any fish show signs of flicking and rubbing?
Do any fish dart around the tank?
Do any fish swim in a jerky movement?
Do any fish gasp, or signs of laboured breathing?
Any excess slime on fins, body, gills?
Also check for tiny red pin prick marks on body, fins, gills.
Do any fish look thin, or bloated?
 
Just looking to see if the red gills are caused by parasites.

 

[pirategrl]

API freshwater master test

One ram showed labored breathing. The others were eating and acting fine and when I woke up they were dead. No one is bloated or thin. All dead fish were very slimy but I don't notice anything on the others. I do not notice any itching thrashing or red pin pricks. One of the golds did have its eye popped out when we found him but the night before it was normal. The neons kind of dart at each other but that's been their behavior since we got them.

 

[WILDER]

Sorry been away.
How are the fish now?