CO2 usage, Gone too fast?

[Dutch]

Ok, so here is another stupid question. I recently went from using Reactors to a NW setup. Tank size is 155 gallons. I have the CO2 dialed in now where everything is right, however...

I use a 20# tank of CO2. In the past a full tank would last me about 3 months. When I changed over to the NW setup, the full tank lasted barely 30 days.

hmm... Can I really be outgassing/losing that much CO2? I have leaked checked everything (shut off the tank, primary and secondary gauges did not move with solenoids turned off for 30 minutes) and can find no leaks on any fittings. This leads me to believe one of two things. First, the tank was not filled correctly, or second, I am wasting a lot of CO2!

The tank is run off of 2 solenoids. The first one is a steady 4 bubbles per second through an electronic valve (CO2 Doser). The second is just a solenoid and needle valve. Both are plugged in to a timer that comes on 90 minutes before the lights-on for a total on-cycle period of about 11.5 hours/day. The outputs of both are fed into a single line that attaches to the NW pump inlet (mag 18 fractioning). Flow back to the sump is with a sealed overflow box, into a sealed wet/dry sump. When the system is running there is a ton of tiny bubbles throughout the entire tank.

I'm thinking of putting back inline a reactor chamber to maybe help dissolve some CO2 before it hits the open tank?

Ideas? thoughts?

Thanks.

 

[gsjmia]

I know you said you checked for leaks, but unless you are blowing millions of bubbles a minute I don't see how you could empty a 20lb tank in a month without a leak-or it wasn't full to begin with.

Leaks are very sneaky and hard to find. I don't think a 30 minute shutdown test is long enough.

After the solenoids are off, mark the needle positions with a mark on masking tape and shut the tank valve and let it sit overnight. If no leaks, it should still have its high and low side pressure.

You didn't say if you are using a perma seal thing, but I hate those things. They leak and are sometimes hard to find around the CGA nut or flange. I have been using the same fibre washer for over 8 years on my Co2 carbonated soda system.

It doesn't take much of a bump or a jostle to create a problem.

As far as the filling goes, they fill them by putting the tank on a scale and then filling it by weight. Seems unlikely it wasn't filled, but possible. On my 20's, I can lift an empty tank with two fingers, but have to use my whole hand when its full. If it wasn't filled all the way it would have been noticeable.

I vote for the leak.

You got a frustrating sitiation and it could cost a few bucks before you find the solution.

 

[Tom Barr]

It's a leak.

You need to find it.

Simple as that, tough to find some of them, but...........that's the only way.

Most common: solenoid, the gasket from the tank to the regulator, around the air line, check valves etc.

 

[dutchy]

NW setups drive up CO2 consumption bigtime. I'm not surprised. I use around 10 lb per 6 weeks with two reactors on my 180.

 

[GillesF]

Get this, works extremely well: http://www.swagelok.com/products/leak-detectors-lubricants-sealants/snoop-liquid-leak-detector.aspx

 

[fleuramore]

Not sure if this would work or not for locating a CO2 leak, but you may want to put some soapy water on the areas you think the leak may be coming from. When you see bubbles, there is your leak. Just a thought as this is how I found out where the natural gas leak was outside my house.

Faith

 

[Dutch]

Well i shut the valve off on the tank and let it sit overnight, no drop in pressure so I'm thinking everything on the pressurized side is ok. I did notice something right off though, when I changed out the tank, I also did a massive cleaning on all the hoses, pumps, filters etc. When I put them all back to work, the powerhead I had pointing up for surface ripple was not agitating the water as much. I left the CO2 settings as they were set before and sat down to work a bit. I came by and checked the tank after a couple of hours and noticed all of the fish were at the top of the water and stressed out. Turned off the CO2 and put an air pump in to get some O2 in the tank. It seems like I had the CO2 cranked way too much, and it was gassing out from the surface ripples? I've since left the powerhead where it was at as the water surface has a little ripple in it now and the top stays clear. I've turned the CO2 way down as well (secondary now set around 7 instead of 12) and the tank no longer looks like a bubble factory. Still have very fine bubbles everywhere, a lot smaller than before. Drop checkers are showing almost yellow, and some plants are pearling.

I did tighten all the regulator fittings and checked the joints with soapy water (ty for the tip). Guess i will wait and see how long this tank lasts and go from there.

ty for all the feedback.

Still thinking of putting a large reactor chamber after the NW pump to help dissolve the bubbles a bit more.

 

[dutchy]

Putting a reactor after a NW doesn't work. The bubbles are already so small that the reactor will let them pass without diffusion.

 

[gsjmia]

Dutchy, once I put a few pot scrubbers in a reactor and it eliminated the bubble pass through.

I presently have an Up Aqua atomizer but it seems to be limited to a certain amount of Co2 before it gets overwhelmed and then starts putting out bubbles.

I was going to revert to the reactor/pot scrubber (hate bubbles)-any suggestions or know of a better way?

 

[dutchy]

No, to me a reactor always has been the most efficient. Various internals may work better but might also restrict flow.

 

[Dutch]

Well i ended up putting the reactor in-line just to try it. The reactor is actually one of those large whole house filters that I modified. With just bio balls in it for diffusion, it has drastically cut down on the amount of bubbles that I see in the tank. I will try pot scrubbers next and see if that helps. Overall though, I have been able to turn down the CO2 output and still maintain the levels in the tank that I need. best of both worlds? the NW really breaks up the CO2 and the agitation in the reactor churns it up until most of it is gone.

 

[Gerryd]

Sounds like a winning combination....I like the fact that you tried it instead of just wondering..

Some pics would be nice...

 

[Dutch]

The filter canister has 1in inlet and outlets. I drilled out the middle and extended the outlet down to the bottom of the canister offset to hold the pump inside which is a maxijet 600. Drilled a hole in the top for the pump power cord and sealed with silicone. Removed the air bleed valve from the top and threaded in a fitting to attach an airline which feeds back into the sump pump inlet (any excess gas will be returned). Currently have the bio balls inside, but plan to replace those with pot scrubbers.

The maxijet inlet grabs a lot of the bubbles churning around in there and pumps them up to the top. The pump acts to agitate the water inside the canister to dissolve the CO2.