High nitrate, fish breathing fast

[sam555]

I have got a 34 litre tropical tank with 2 botia striata's, 2 tiger barbs and 1 red tail black shark. They have been breathing quickly for a while and the nitrate level is high. I do water changes of around 25% every week and yesterday I put an under gravel filter in as well as the normal filter which I thoroughly cleaned. I have an air pump in the tank but they still breath fast. Does anyone know what could be happening and how to fix it

[MainelyFish]

I would try doing several larger water changes more like 50% and see if that helps... I had high nitrate and i was doing larger water changes and that brought it down over time...

[Obsidian]

Was the tank cycled?

[sam555]

The tanks been cycled for 3 years but I've had the problem for about 3 months.

Thanks mainlyfish I will try that. But will that solve the fast breathing?

[weedkiller]

have you checked your source?
tap water parameters can change fairly quick if main works have been going on

[mousey]

what do you mean by "thoroughly cleaned the filter"??
How big is that shark?

[sam555]

The shark is 12 cm long and by thoroughly cleaned I mean all the scum is off of the carbon and the filter sponge but I cleaned it using the existing water so I didn't get rid of the bacteria needed.
I don't think it's the source because my brother uses the same water and his is absolutely fine and none of his fish are breathing fast

[weedkiller]

look past the high nitrates as it may not be the nitrates causing it, ive suffered with high nitrates for a long time and jst got them under control with r.o water and matrix bio filter and not had the same issues, if your fish are compatible to a salted tank try adding aquarium salt to the ratio is says on the packet, (not in one hit mind, add it gradual) salt helps with gill function and helps keep them healthier,
don't overlook any other obvious signs either as you may be presuming its nitrates because they are there

[Angelclown]

Ok, I have high nitrates and my fish don't breathe fast. I have sensitive fish.

I would check your ammonia and nitrite, as these can cause fish to breathe fast. Also stress can cause fish to breathe fast.

[sam555]

The nitrite, ammonia, ph, gh and chlorine levels are all fine and in the safe zone. I will try putting salt in my tank

[mousey]

38 litre tank is not very big for the shark. Perhaps you are running the extra nitrate because you have a bigger fish in a small tank.
That happened to me when I kept a mature Bn pleco in a 5 gallon (20 litre) tank. He was alone but I couldn't get the ammonia under 1 unless i did daily water changes. The nitrates were also elevated too high unless I did daily water changes.
Visually a 4-5 inch (approx 10cm) pleco is not that large in a 5 gallon tank.

[sam555]

Originally Posted by mousey 38 litre tank is not very big for the shark. Perhaps you are running the extra nitrate because you have a bigger fish in a small tank. That happened to me when I kept a mature Bn pleco in a 5 gallon (20 litre) tank. He was alone but I couldn't get the ammonia under 1 unless i did daily water changes. The nitrates were also elevated too high unless I did daily water changes. Visually a 4-5 inch (approx 10cm) pleco is not that large in a 5 gallon tank.

Would this affect their breathing?

[lohachata]

if there is carbon in the filter cartridge , get rid of it...never use carbon for more that 2 or 3 weeks..i would also suggest a couple of 50% water changes and the addition of an air diffuser...
once carbon becomes saturated it will start to leach toxins back into the tank poisoning the fish...just might be your problem..or part of it.
but i agree...the tank is pretty overstocked.

[sam555]

Cossie's tank is the exact same as mine with the same filter and everything but his is absolutely fine with no fast breathing. I will try the water changes but It won't be the carbon because my carbon is relatively new.

[lohachata]

how new ?? within the past 2 weeks ?
the tanks cannot be exactly the same...whatever it is that is different is causing the problem..
identical fish..gravel..decorations..there is something different...