does Co2 distribute in a tank evenly?

[JackBlasto]

I have a tall tank (3 feet deep). Was wondering if the Co2 gets to the bottom of the tank efficiently once it's injected or is it more concentrated at the top? I have no powerheads but the water comes in from a pump out of a sump and is pushed into the tank (almost like a power head). If my tank was a normal height I wouldn't even wonder if this could be a problem but I was wondering if there were any CO2 guys out there that had a feeling for this.

 

[JackBlasto]

To further elaborate... I guess its the reactors job to dissolve the co2 so in theory if the reactor is efficient than anywhere there is water there would be a good co2 level. Yay or nay to this theory of mine.

 

[meegosh]

What kind of sump is it? I would think the sump would off gas a lot of the co2... But, yes, the reactor should get it close to 100% dissolved in the water column. From there your pumps do the circulating.

 

[JackBlasto]

Sump is a herbie overflow style leading into a refugium style. There is a lot of debate on whether or not a sump gasses off your co2. Wet Pets in Pennsylvania has planted discus show tanks all with a sump refugium style and they swear by them.

 

[JackBlasto]

And yes their tanks have co2 injected. I guess the gray area in whether run off exists is how the layout is done. I wouldn't think a drip over bio balls in a wet dry system would be a good choice but...

 

[meegosh]

Interesting.. Was curious to see how it worked with a sump. Zagz on here had a trickle filter on hers and remember her having some issues.

I've heard great things about Wet Pets. One day I'll have to stop in and see what the fuss is about.

 

[JackBlasto]

Yeah, you really need to go there and see since you are pretty close. I'm in Morgantown WV and make the hour drive to get my stuff there just because it's HEALTHY

Anyway, the reason I was wondering about distribution rather than run off is plants on my driftwood (dwarf baby tears higher up in the tank) pearl like crazy through the day. The plants at the bottom of the tank (dwarf baby tears just about 10 inches lower) don't pearl as of late. This might be because of the light difference in that 10" or possibly the CO2 wasn't getting all the way down there but there was something causing the dwarf tears to be doing a lot better higher in the tank.

Thanks for the feedback on the reactor.

 

[meegosh]

Assuming you have decent flow, I would think the depth would be your problem. A three foot deep tank takes some serious lighting to get down to the ground cover.

 

[JackBlasto]

Yeah, I have seven t5 bulbs which span the entire hood. The guy that sold me the equipment at aquarium plants .com weighed into consideration the depth of the tank and maximized every square inch of hood I could use cutting an extra light fixture to custom fit the cabinet. He told me the end result was 4 watts per gallon. The lights are BRIGHT. I can barely even look at them. Anyway, I understand the depths are something people warned about. Makes sense and it's crazy upkeep and set up BUT wow does it make a spectacular display for that added height no one wants to deal with. It makes for a tank unlike anything I've seen. My guess is the lighting at the bottom is adequate but clearly less than mid tank, thus the difference in pearling now that you've pointed out some key things going on. Thanks.

 

[aqua_chem]

CO2 will be highest where you have good flow and lower where you have poor flow. If you have good flow throughout the tank, it shouldn't be a big issue unless you have a really large tank (in which case two points of injection might be an option). If you have poor circulation, or overgrown plants blocking flow, then you might run into localized co2 issues.

I agree that a wet/dry filter is probably a bad idea. Anything that increase gas exchange will kill your co2. Have you put a drop checker into your tank to determine if you're getting appropriate co2 levels?

 

[JackBlasto]

Yes theres a drop checker positioned about 4 inches down that reads fine. Maybe I should reposition it deeper in the tank and see if theres an effect.

BTW the tank is 100 gallons... really 98 gallons... dimensions are 36"wide x18" from wall to front x36" tall (looking at it a giant square)

 

[aqua_chem]

Not a bad idea.