Why use a Solenoid valve?

[ghostsword]

Today I got a scare on my tank, for the first time all my fish were on top gasping for air.

I setup the solenoid to stop CO2 at 2200 and start it again at 0530. It must have dosed too much CO2 into the tank, as at 0700 they were all gasping for air.

I turned the air pump on and lit the lights, so that the CO2 drops during the day, and will check it again at night to see if I can get to a balance.

Some fish I do not mind loosing, such as as the platies, but I really like my dwarf neons. Should be ok, but I was not expecting it with the solenoid. I was expecting some sort of lack of CO2, as it was stopped at night, not this.

 

[Mark Evans]

Some fish I do not mind loosing, such as as the platies

you should be concerned for all fish my friend.

 

[ghostsword]

Some fish I do not mind loosing, such as as the platies

you should be concerned for all fish my friend.

I should, I know I should .. and I do not want to cause them suffering, but there are some that are my favourites..

 

[Ajm200]

I hope the fish are ok. A quick water change helps in that situation. Maybe you can turn the co2 off a bit earlier to give the fish a break. I may be wrong but the plants shouldn't need the co2 on for that long. Turning it off a bit earlier an hour or two before the end of the photoperiod will allow the plants to use up some of the excess making it easier for your fish to cope when the lights go out and the plants start using oxygen and releasing co2.

I now have the co2 on several hours before the lights go on and turn it off 3 hours before lights out. Still got a shock a couple of weeks ago when I tried to add new fish hours after the co2 stopped and nearly lost them as the co2 levels were still too high for them.

 

[ghostsword]

Thanks,

All the fish are ok, and there were no losses.

I will turn off the CO2 two hours before end of photo period, at 2000, and then allow CO2 to start again at 7am, an hour after air pump gets turned off.

The air pump starts at 0000 and turns off at 0600, so that gives the fish a break.

The tank is not big, so the onus is on me to sort it out.

It was working perfectly when I had the CO2 24/7 and the air pump only at night, so it is odd that problems started when I added the solenoid.