angels and O2

[Yoemen]

I have heard recently that you need to be careful with angel fish and o2 levels.

Well last night I got home at about 1 am and the lights were off on my aquarium, I looked in it and saw one of my angels looking a little listless. I turned on the lights and he was really dark. The other 2 angels didn't move either. I dropped some micro crabs in the tank and they didn't respond. I even stuck my hand in the water and they didn't react.

I quickly adjusted my eheim spray bar to where it caused some surface agitation and the Angels recovered and began swimming again and returned to their color.

I have dialed back my CO2 to 15 ppm just to be safe and left my spray bar where it was.

Are there any steps to take in regard to being careful with angels in regard to CO2.

I have realized this morning they may have just been asleep, but they generally react when the light comes on in these cases.

This is a 75 gallon heavily planted CO2 injected aquarium.

Thanks for the help.

 

[wolf13]

Plants use O2 at night when the aren't using photosynthesis. I ran into this problem and had a good scare with my tank, and have since added a t to my airline and an air pump during lights out for surface agitation, otherwise with a decently planted tank it is very easy to deplete the oxygen. it shuts off about 45 minutes before lights on with the co2 coming on, and i shut the co2 off a good bit before lights out to let the plants use up some of the remaining CO2 rather then just degassing it.

 

[Mgamer20o0]

i have my co2 on 24/7 with a tank full of plants and angels no problems.

co2 and o2 are independent of each other.

 

[Yoemen]

Ok, so did I just need so surface agitation to increase the amount of O2 in the water or what?

 

[Mgamer20o0]

if the fish are not gasping they should be fine.

 

[Yoemen]

well they were all hanging around the surface of the tank.

 

[Mgamer20o0]

sleeping and hanging around is different then gasping. do they look like they are pecking at the surrface trying to get air? you could run a test. put a air pump on the tank for a night see if they still do it.

 

[Yoemen]

they weren't so much peking, it was like they were putting their lips to the surface. They haven't done it since I moved one of the spray bars to the surface.

 

[PopPopsfish]

I ran into the same problem about two days ago, I raised the spray bar to increase the O2 and everything is now fine. I have a pair of prize breeders in a 46 bow and 5 large amazon swords. At night the O2 level decreases so I have added an air stone to bring the O2 level to a safe place. I made my own CO2 generator out of a 2 liter soda bottle, I was tired of spending all that $ on Co2 supplies.