HELP! All my fish are gasping at the surface

[apotocki]

Please help. I have a problem in my 70 gallon. Here's my story.

Yesterday around 2pm I decided to do a PWC(about 25%)/light gravel vacuum and clean about 1/2 of my plants (silk and about 9 of the 18 total). This went well although it did take me about 1 hour. My tank is relatively new being up and running for 9 weeks now and this is the seconed time I've lightly cleaned and vacuumed as I did the first 1/2 of the tank about 1 week ago.

All appeared fine until about 10pm last night....I noticed all the fish huddled in a corner at the surface gasping for air and breathing very fast. I immediately performed a 30-40% water change and tested the water (I have been testing everyday andanyway) and had no water problems (0 ammonia, 0 nitrite, about a 5 nitrate, 7.0 ph, and temp of 79. After the PWC the fish went back to acting 'normal'.

This morning, I looked at the tank before turning on the light and all the fish looked ok. As soon as I turned on the light, they all went to the surface and starting gasping again. I just performed another 30-40% PWC and they look good again.

The tank is stocked as follows:
6 Rasboras
7 Rummy's
5 Bleeding Hearts
2 small Angels
4 Cory's
2 small Clown Loaches
1 small Pleco

Any idea's and what else should I be doing besides frequent PWC (if anything?)

THANKS!

 

[aquanaut]

Do you have enough airation. If they are gasping at the surface there must not be enough air present. Just a thought.

 

[Devilishturtles]

When you cleaned the tank, any chance some sort of contaminant could have gotten in there? When you filled your water back up, was it the same temperature as the water in the tank?

 

[BrianNY]

And are you treating the water for chloramines when adding new water?

 

[apotocki]

Ok....I thought about the aeration thing....I don't think that is a problem as up until yesterday they were fine. Unless becasue I've cleaned/vacummed the tank and caused more sediment in the filter, the outflow is being reduced and not circulating the surface as much as before? I have an XP3 canister and had not rinsed any media as of yet.....maybe I should rinse the mechanical media?

I use a Python and add Amquel + to the water as I refill it and frequent check to be sure the new water is the same temp.....so I think that probably isn't the problem either.

Ahh, the contamination idea. Hmmm...maybe. I did have my whole arm in the tank (and since its a 70, it's 26 inches tall) for quite sometime. Maybe soap residue from my shower or deodorant (?).....I guess at this point, that's about the only thing that I can think of. Should I just keep performing PWC's? IF so, how much and how often?

I just fed the fish and they ate and acted normal.

Thanks!!!

 

[Guest]

Are you SURE your tank is cycled?

 

[apotocki]

Yes, I am positive that the tank is cycled.

My Nitrites went to 0 about 2 weeks ago and I've had between 0-5ppm of Nitrate since.

 

[apotocki]

Update: After this morning's 30-40% PWC, the fish went back to their 'normal' activities (eating and swimming/schooling).

I've been watching them alot today and noticed that they appear to be breathing very fast (although they show no other different behavior). Maybe it's just me but I'm thinking that I'll do another PWC later this evening.

I'm really leaning towards the contamination theory. My question now is how many/much PWC can you do before affecting the filtration (biological)? So far, I've done 2 PWC's of approx 30-40% in the past 24hrs since they began exhibiting the gasping behavior.

Thanks for all of your help/assistance.

Alan

 

[anna8297]

Have any of your fish been recently added? I noticed your tank is only 9 weeks old. Is it possible that a new addition was sick when you added it? Do they have any other symptoms? Just a thought.