film on water and dead fish

[Pallen81]

This morning I found one of my banded Rainbows dead. The other banded rainbow is breathing extremely rapidly. I saw this last night and did all my tests. Ammonia = 0 Nitrite = 0 Nitrates under 20ppm. pH 7.2

There is a small layer of film floating around on the surface of my tank. I have put nothing new in my tank and the tank has been running for about 6 years. In a few hours I’m going to do an emergency water change. I assume they are not getting enough oxygen hence the rapid breathing; however none of the other fish in my tank seem affected at all. There is no funny smell to the water. It’s strange.

Does anyone know what this film could be?

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55 gallon
5 Assorted Rainbows (1 banded died this morning)
2 Silver Dollars
3 Zebra Danios
1 Tiger Pleco
6 Ghost Shrimp

 

[Star_Rider]

I've seen film caused by dust..

how old was this rainbow?

 

[Pallen81]

I've seen film caused by dust..

how old was this rainbow?

I had him for about 2+ months. He was about 3 1/2 inches long. I looked at his dead body for signs of something. No red gills, no bloat, his colors were good, no nothing. He looked 100% healthy except for his rapid breathing.

 

[teriba]

Are they getting enough oxygen from surface turbulence? Usually if you have stagnant water it will develop a film and will become very low on oxygen.

 

[wataugachicken]

how long was the rainbow in the tank dead? film on the water is from proteins - it could be from slight decomp of the fish, or just because you don't have enough surface agitation to break it up. the potential for a little *oil slick* is always there is you have fish, but usually it gets broken up by water flow and doesn't have a chance to build up enough to be visible.

 

[Pallen81]

Are they getting enough oxygen from surface turbulence? Usually if you have stagnant water it will develop a film and will become very low on oxygen.

I don't know. I haven't changed a thing in forever on this tank and they have always had enough oxygen. Suddenly this thin layer of surface film appears with 36 hours and 2 fish are breathing hard and dying.... so I assume its a lack of oxygen from the film.

the water is not stagnant.

I'm going home from work and doing a water change in a half hour. this bites. my fish died so quickly.

 

[Astramorgaine]

Consider the average lifespan of your fish, and then consider the age at purchase... Could be it was just time to go. I'm sorry for your loss. I know it's a fish(like my hubby'll say) but I get so attached!

 

[Pallen81]

Consider the average lifespan of your fish, and then consider the age at purchase... Could be it was just time to go. I'm sorry for your loss. I know it's a fish(like my hubby'll say) but I get so attached!

yeah thanks. its a bummer. This fish was def still a juveline. So he it wasn't his time to go.

There has always been enough agitation of the surface to create enough oxygen. I don't know why it would suddenly change without warning.

this fish died sometime during the night and I took it out at 7:30am when I got up for work. the film was there the night before and the fish couldn't have been dead for too many hours before I saw him.

What causes this film to form?

 

[Pallen81]

I just did a water change during my lunch break (the whole lunch break hehe) and my banded rainbow is still struggling to breath. he is rapidly breathing. in addition to him, my largest australian rainbow is breathing a little heavy as well. All other fish in the tank do not seem affected. seems only the larger rainbows are affected.

I did about a 25% water change and added a few teaspoons of aquarium salt (which I never use) to hopefully help aid better gill function.

any other ideas? lower the temperature means more oxygen right??? should I do that or just let things even out.

 

[wataugachicken]

did you happen to do a water change last night before you saw the heavy breathing begin? i wonder if, since water changes aren't helping, maybe something has changed with the tap water itself? any heavy rain or snowmelt going on in your area?