Hi all, bit of a dilemma!
Fed my fish tonight at 8pm, all were fine and eating. Come to bed at 10pm and I had two dead barbs, all the rest were gasping. One barb seems to have blood around its mouth, the cory's were darting to the surface for air and I can't even see my algae eater. I don't know what has happened, both filters are on. I immediately did a 50% water change as there is clearly a lack of oxygen going on, pulled both filters up to give as much of a ripple to the water surface. They've all calmed down now, gills have slowed right down and swimming around but just don't know what could have happened in the space of a couple of hours.
I'll be going to the LFS tomorrow to buy some test kits (typical time to run out) but there is no reason for any spikes or problems (never had any ammonia/nitrite etc readings over the 2 years the tank has been set up). Other then what I've described there are no other physical symptoms present and watching them now you wouldn't think anything had happened.
Thanks for any help.
Oh and for further information - its a 65 litre tank, two internal filters and (possibly a cause but I don't see why) I started using liquid carbon and ferts last week but I have kept below the dosage guide (and forgot to put any in today anyway) surely 1ml of liquid carbon has completely starved the tank of oxygen?!
Fed my fish tonight at 8pm, all were fine and eating. Come to bed at 10pm and I had two dead barbs, all the rest were gasping. One barb seems to have blood around its mouth, the cory's were darting to the surface for air and I can't even see my algae eater. I don't know what has happened, both filters are on. I immediately did a 50% water change as there is clearly a lack of oxygen going on, pulled both filters up to give as much of a ripple to the water surface. They've all calmed down now, gills have slowed right down and swimming around but just don't know what could have happened in the space of a couple of hours.
I'll be going to the LFS tomorrow to buy some test kits (typical time to run out) but there is no reason for any spikes or problems (never had any ammonia/nitrite etc readings over the 2 years the tank has been set up). Other then what I've described there are no other physical symptoms present and watching them now you wouldn't think anything had happened.
Thanks for any help.
Oh and for further information - its a 65 litre tank, two internal filters and (possibly a cause but I don't see why) I started using liquid carbon and ferts last week but I have kept below the dosage guide (and forgot to put any in today anyway) surely 1ml of liquid carbon has completely starved the tank of oxygen?!
