[mmfish]

Any experience with open top tanks and difficulty with maintaining CO2? I have a 47inch by 32inch tank and have difficulty with such.

Thank you,

 

[HypnoticAquatic]

open top will not really matter what will have a much greater effect is your water movement and agitation. if your not getting enough co2 into the water id look at your diffusion method and flow rate but a lot more INFO in needed like type of co2 diffusion, bubble rate, tank size, light, surface agitation, filter type, ext ext that will help others get down to why your not getting proper co2 levels

 

[150EH]

CO2 is a gas that can get thru the smallest of cracks, so even in a sump I don't see what difference it makes trying to cover it up. But it's most likely your delivery method is very ineffiecient, what do you use to get CO2 in your water??

 

[mmfish]

I use a "carbon doser 5000" which is the water filter canister system inline with an eheim canister. pH is controlled with a solenoid and profilux controller.The return opens 2 inched below the surface.

 

[zergling]

Like 150EH said, it's all about CO2 diffusion, surface agitation, and good flow to distribute the dissolved CO2.

Google Amano's ADA tanks. They're all open top.


EDIT: How much of a pH drop are you getting? In my tank (48"x18"x18"), my pH during the lights on drop all the way to 6-6.2. The tank water I took out and let sit for 24 hours test out to pH 7.4. While pH drop isn't the best way to measure dissolved CO2, it's a good starting line.

 

[mmfish]

Like 150EH said, it's all about CO2 diffusion, surface agitation, and good flow to distribute the dissolved CO2.

Google Amano's ADA tanks. They're all open top.


EDIT: How much of a pH drop are you getting? In my tank (48"x18"x18"), my pH during the lights on drop all the way to 6-6.2. The tank water I took out and let sit for 24 hours test out to pH 7.4. While pH drop isn't the best way to measure dissolved CO2, it's a good starting line.

Meaning less to no surface agitation? Some is needed in a planted tank

 

[fishykid1]

Yeah, you need some agitation when injecting a lot of co2. Otherwise your just going to go over what most fish can handle. Some debated the max is around 40-50ppm, but I've never found a perfect co2 measurement; estimated guess at best.