I got home from work today and was checkin out my fish. I soon noticed a danio dead, just inside my castle. He didn't appear to have any trauma. No "prickly" scales, no signs of ich, and he wasn't thing at all. He did happen to be very vale lookin in his midsection (just behind "neck" and to beginning of back fin). Its stripes seemed almost washed away, kind of. While doing a fish count I found another danio! I tested my water and the only thing elevated was the ammonia to about .25 or less (liquid API test). My ph almost is always at about 7.6 or so. other than that my nitrites, nitrates are both at 0 and .5 or less, respectively. I think I found the reason my ammonia was up, is due to the red wag/platy I found dead too!! I just got the platy about two or three days ago. and now its dead! It was fine last night as well. I've had my danios for about 6 months now too.
if anyone has any input, I would really appreciate it!
btw, I attached a link to the youtube video I mad about an hour ago of my danio. I couldn't get the video to upload here. That's why the youtube.

Thank you for your help!
-James

__________________
"May I never wake from the American Dream."
-Carrie Latet

60 gallon
5 Orange/Sunburst Platy
1 Angelfish
1 Silver Tip Tetra
2 Glass Catfish
4 Zebra Long Fin Danios
2 Siamese Algae Eaters (SAE)
2 Amano Shrimp
2 Fancy? Tetras
1 Green/Ghost pleco
Hygrophila angustifolia
Anacharis
Swords: 1 Melon, 1 Amazon, 1 Rose
Micro Sword
Moneywort
Rotala nanjenshan
Anubias barteri/Broad Leaf
Brazillian Pennywort

and some I forgot the species of...

When all else fails, do a water change. Hard to say what you're problem may have been. Do you always test positive for ammonia?

I already did a 30% change today. I don't normally, but, I think it may have been the dead fish from last night/today. Those maaaaybe died from...? I had a shrimp die from not eating sometime while I was out camping. it could have been two days or three that it was in there. maybe that killed the others???

__________________
"May I never wake from the American Dream."
-Carrie Latet

60 gallon
5 Orange/Sunburst Platy
1 Angelfish
1 Silver Tip Tetra
2 Glass Catfish
4 Zebra Long Fin Danios
2 Siamese Algae Eaters (SAE)
2 Amano Shrimp
2 Fancy? Tetras
1 Green/Ghost pleco
Hygrophila angustifolia
Anacharis
Swords: 1 Melon, 1 Amazon, 1 Rose
Micro Sword
Moneywort
Rotala nanjenshan
Anubias barteri/Broad Leaf
Brazillian Pennywort

and some I forgot the species of...

I doubt .25 ppm ammonia killed anything in your tank. I know we don't want any in our water but that small ammount would be harmless to most common fish. Just mho and some experience with ammonia levels higher than that.

I assume this was in your 40g tall and that it is a fully cycled tank. btw, what were/are your NitrIte level?

__________________
60g tall, all artificial plants, Rainbow tank; 55g for African Cichlids. 20g long for fry; 20g hex, 2 black Angels at my desk; 10g planted, with 50 Molly fry; 10 gal, 2x 13w cfl lightning, planted; 2g hex for "Buddy the Betta"; Wanting a 200g +, MTS getting bad.

Since this post I've been able to reduce ammonia to 0. The nitrites as well are at 0. From what it seems, that danio is doing much better. I'm at a loss.... I did end up losing my red wag though. It turns out that my sunburst had a fry that lived tho

__________________
"May I never wake from the American Dream."
-Carrie Latet

60 gallon
5 Orange/Sunburst Platy
1 Angelfish
1 Silver Tip Tetra
2 Glass Catfish
4 Zebra Long Fin Danios
2 Siamese Algae Eaters (SAE)
2 Amano Shrimp
2 Fancy? Tetras
1 Green/Ghost pleco
Hygrophila angustifolia
Anacharis
Swords: 1 Melon, 1 Amazon, 1 Rose
Micro Sword
Moneywort
Rotala nanjenshan
Anubias barteri/Broad Leaf
Brazillian Pennywort

and some I forgot the species of...

Sustained low levels of ammonia can harm. Unlikely to kill healthy fish maybe, but.....more sensitive would be more susceptable.

good to hear! I just got a zebra danio today. Just one. :P

You should get more than one. If it's alone then it may be okay. I had one of mine in the nurse tank to grow it's rear fin back, for a month or so. It became semi-agressive after that. (may have been a vengance thing though lol) Either way, they don't seem to do well when in groups of less than 5.

As far as my danios dying, they have since stopped. I've estocked them to a school of 6 and they've been fine since OP. My ammonia seemed to read at 0-0.25. Its a very fine difference between the color shades. Its pretty much at 0 now though. My fishies are happy lol

__________________
"May I never wake from the American Dream."
-Carrie Latet

60 gallon
5 Orange/Sunburst Platy
1 Angelfish
1 Silver Tip Tetra
2 Glass Catfish
4 Zebra Long Fin Danios
2 Siamese Algae Eaters (SAE)
2 Amano Shrimp
2 Fancy? Tetras
1 Green/Ghost pleco
Hygrophila angustifolia
Anacharis
Swords: 1 Melon, 1 Amazon, 1 Rose
Micro Sword
Moneywort
Rotala nanjenshan
Anubias barteri/Broad Leaf
Brazillian Pennywort

and some I forgot the species of...