O2 levels

[mmasuda31]

any suggestions how to keep 02 levels up without keeping a light on all the time?

[itsthesong]

Agitating the surface of the water with a powerhead to increase the transfer of H20 and CO2.
Open windows (in the summer) to allow transfer of air.

[WaterKeeper]

Well mM,

You will notice bubbles coming off the rock and sand when the lights are on. That is oxygen being emitted by the algae in the tank. Also, if you have a skimmer or sump,you are adding a ton of O₂. It is only at night that one worries about low D.O. as without the lights out the algae produces carbon dioxide instead of oxygen. The circulation in your tank should remove the carbon dioxide and keep the tank oxygenated. Even at night , I'd skip the Diver Dan and count on the skimmer and sump for aeration.

[mmasuda31]

WaterKeeper,

Thanks for your input. I've got a 28 gallon bowfront. That is at the end of its cycle. All perameters spiked, and have come back down. I added 2 small dansels, a week ago. 1 yellow tail and 1 4 stripe. The strpie died within the day, and I noticed when I keep the lights out and come home the yellowtail is very sick looking in color and demenor, he just kinda floats around with the current bouncing into walls. I purchased a clean up crew last night to moderate the algae levels to cut down on CO2 production and they all seemed to be doing well when I woke up. Ph was at 8.3, as a reasult of a 20% change before I added the crew. I know I need to moderate light usage but am a little paranoid since I added a couple shrimps and a crab and snails. (btw one of the peppermint shrimp got caught in a water pump and died) perhaps I have too much flow, although I understand thats not possible. This is my first crack at a salt water tank, and im trying to be wary of some possible obsticles, as i've seen some people with nightmare stories. I do want to add a couple fish soon, and thought perhaps o2 might be an issue.

[bertoni]

If the pH is at 8.3, the tank is fine as far as CO₂. I suspect the oxygen level is fine, but Salifert makes an oxygen test kit you could try, if you want to be sure.