Too Many Deaths?

[mhancock]

[background=rgb(250, 246, 237)]I've had 4 fish die in two days in an established community tank, 225l. Water is consistently showing pH7, and zero ammonia, nitrates and nitrites. The tank is well filtered and heavily planted.[/background]

[background=rgb(250, 246, 237)]The fish that have died are two cardinal tetras, one medium sized angel and a clown loach. I've also lost an elderly male molly but he has been looking like the end is near for a few weeks so not too concerned about that one![/background]

[background=rgb(250, 246, 237)]What I cannot work out is why - it could be coincidence but seems too many, and the only things that have changed are:[/background]

• For three days the fish were with no extra light as the bulbs blew in the hood
• I've got the CO2 line working properly
• When installing the CO2 I used a tiny amount of detergent to clean the diffused, and rinsed it very well

[background=rgb(250, 246, 237)]I'm assuming that a minute amount of detergent got into the tank so did a large water change and will do another, rather than 3 days with no hood lights or the extra CO2 being a problem.[/background]

[background=rgb(250, 246, 237)]Any other thoughts?[/background]

[background=rgb(250, 246, 237)]Thanks,[/background]


[background=rgb(250, 246, 237)]Mark[/background]

 

[daddyvitax]

Is the co2 for the plants ? try taking it out for a few days and add a air pump to increase the oxygen for the fish. Also check your filters are clean and you dont have a nitrate build up as thats a big fish killer. hope this helps

 

[mhancock]

Thanks, have lots of air coming through, it turns out that the problem was CO2 running with lights not working leading to too much CO2 in the water.

 

[Mikey1]

yes i would say thats "too many"

thats more fish than i lose in about 2 years!

 

[CezzaXV]

I think the problem may be the CO2. With your lights not working, your plants won't be using the CO2, and your fish probably suffocated. If you can't get the lights working, turn off the CO2 for the time being.