powerhead question

[craqerjaq]

I'm not sure if all powerheads are like mine but it has an airhose coming off with a little valve control which hangs outside of the tank...I open it and air bubbles get circulated through the tank.

My question is what is the purpose of the air bubbles being pushed into the water from the powerhead? I'm not sure if I should leave the air valve closed or open or open it occasionally or not...is it a good or bad thing?

[LAReefs]

Sometimes the bubbles are used for skimmers or co2 injection for planted tanks. I would stay away from using the venturi in your case since you don't want micro-bubbles lingering around in your SW tank.

John
LA Reefs

[craqerjaq]

sounds good thanks

[Ninong]

I'm not sure if all powerheads are like mine but it has an airhose coming off with a little valve control which hangs outside of the tank...I open it and air bubbles get circulated through the tank.

My question is what is the purpose of the air bubbles being pushed into the water from the powerhead? I'm not sure if I should leave the air valve closed or open or open it occasionally or not...is it a good or bad thing?

Let's say that you wanted to mix a batch of saltwater. After stirring it well to dissolve the salt mix, you might use a powerhead to aerate it.

Never do that with limewater (Kalkwasser). You do NOT want to aerate limewater. After stirring it, you tightly cover the mixing container and let it sit undisturbed for several hours before siphoning off the clear liquid without disturbing the sediment in the bottom.

[craqerjaq]

limewater?

[Ninong]

Yes, limewater. The German word for that is Kalkwasser (literally chalk water). It's a method used to maintain calcium and alkalinity.

The only reason I threw that in there was so that people reading this thread wouldn't think it was a good idea to use a powerhead to mix limewater because it would be a terrible mistake to do so.