I'm pretty confused (again).

I have a 180G tank and I have had, as you might expect, problems getting enough CO2 into the tank.

I decided to try the misters... so I bought three of the Rhinox 2" diameter misters (these are big). I also invested in some nice needle valves to distribute the gas.

In order to get any bubbles out, I had to crank the pressure up pretty high. The stones are so dense that the pressure has to be high. I tried to blow through the intake and it was a lot harder than say manually blowing up skinny balloons.

So anyway, I get a lot of bubbles in the tank. LOTS of bubbles. Not a lot of growth mind you. But lots of bubbles. The entire top of the tank is even covered in 'em. Well, except where I have some small pumps creating some turbulance to help with gas exchange. The fish are fine. No signs of stress. I even have happy otos.

The problem is that I'm going through CO2 like mad. I have checked the system for leaks (using soap bubbles)... but I don't see any.

Does the mister method use a lot more CO2 than the reactor method? Seems like it must. How many pounds of pressurized CO2 would you expect to use on a 180G say per month?

Thanks! - Chris

I'm using one of the Rhinox misters (forget the model) on a 20 long, and I'm using up a 5lb CO2 canister every 1-2 weeks, depending upon how many bubbles per second I'm using as I experiment. Regardless, it seems to go through quickly! Luckily I have a contact that I can refill at $6, but still, it's a lot more than I thought I would.

I am using one of the Rex Grigg setups with a low-pressure regulator and needle valve. I found I had to tape over the LPR's vent to prevent the gas escaping there. Only recently did I reson that that was where a lot of the gas was escaping.

Also, those Rhinox (or similar) diffusers do not work with DIY CO2 setups, they cannot generate enough pressure.

Generally we used about 20lb tank every 1-2 years using misters for a 150-200 gallon tank.

Leaks etc sound like an issue.

Regards,
Tom Barr