3 Corys Gasping At Surface

[Tracy10]

hi,
I have a juwel vision 180,with an internal juwel filter & tetratec external filter.I have neons,cherrybarbs,glowlights,platies & corys.All my other fish seem fine,alhough i have seen the occasional flicking...but 3 of my 4 corys are gasping at surface,almost constantly.Something is definately wrong with them but i dont know what to do.I cant see anything on them at all,but they are breathing heavy.

Ammonia 0 nitrite 0 nitrate 20 (same as tap) ph 7.4.

Would be very grateful for advice,want to help the poor little chaps.

Tracy

 

[tetraqueen]

Have you an airstone or some way to get more o2 in the tank? I would also try a water change.

 

[Tracy10]

No airstone as the ph rises way to high with one running,but plenty of surface movement from both filters.

I did a water change yesterday,almost certain it was why this happened.I have noticed it does happen occasionaly after water change...but not like this.They really are in trouble.
If it was low oxygen wouldn,t it affect my other fish also?

Tracy

 

[WILDER]

The corys shouldn't be gasping at the top of the tank, the shoot up[ for air now and then.
Make sure there plenty of aeration in the tank.