UP Inline Atomizer Query (400 litres)

Hey,

Installed an inline atomizer yesterday and just have a couple of questions.

Atomizer : UP Inline Large Super CO2 Atomizer
http://www.tankscape.co.uk/co2-and-...Large-Super-CO2-Atomizer-16-22mm-(D-519-16-L)
Regulator : Set to 36 psi as recommended

When CO2 is not being injected, the Atomizer slowly fills with water. Will this happen every time the CO2 turns off? Is it normal?

I'm guessing that when the CO2 starts it pushes the water out of the atomizer?

Are bubble counters useless on tanks this size? I tried between 4 and 6 bubbles per second and nothing happened. I then decided to turn it up, the bubble counter is now a constant stream of bubbles. After doing this a nice fog of tiny bubbles is circulating around the tank. It still took around 2 hours for the drop checker to move away from Blue, maybe it's still not enough. The fish didn't seem stressed and were not at the top. Again, is this normal? Should the tank be covered in a fog of tiny bubbles?

Cheers

Hi,
Unless you install a check valve downstream of the chamber, it must fill with water. The water in the tank has an atmosphere above it pushing down at 14.7PSI (assuming you live at or near sea level). Added to that the water weighs 8 pounds per gallon, so every 33 feet of depth adds another 14.7 PSI just due to the weight. So if your atomizer is located 4 feet below the surface of the water then the total pressure of the water acting in a downward direction is 14.7PSI + (4/33)14.7PSI = 16.48PSI.

In order for gas to flow into the tank the gas pressure, acting in an upward direction must exceed this value. The gas is under pressure and the gauge reading of 3.6PSI is the amount of pressure that is above 14.7PSI, so really, the total pressure of the gas is 14.7PSI + 3.6PSI = 18.3PSI. Therefore there would be a net pressure differential of 1.82PSI in the upward direction when the gas line is pressurized. When you turn the gas off the pressure decays and there is a net negative pressure differential in the chamber so the water floods the chamber.

Stitch said:

Are bubble counters useless on tanks this size?

Click to expand...

Yes. It would be more appropriate to listen to the whistle the gas makes on it's way to the tank, if any.

Stitch said:

a nice fog of tiny bubbles is circulating around the tank....Should the tank be covered in a fog of tiny bubbles?..... It still took around 2 hours for the drop checker to move away from Blue, maybe it's still not enough.

Click to expand...

Yes this is entirely possible. Some people consider the mist of bubbles not nice but that's just a personal thing. It has been theorized that when the gas makes direct contact with the leaves, the CO2 uptake is higher than when the gas is dissolved in an aqueous solution. You just need to observe the tank. If there are no CO2 related issues and if the fish are unstressed, then you have set a good injection rate. As always, one has to play with the injection rate, the gas timing and with the flow distribution to satisfy the needs of the tank.

Cheers,

Clive
Great answer regarding the pressure
hoggie

The UPs will fill with water when not under pressure from the C02, even if you just soak one in a glass of water, the water will travel through the ceramic stone as it is porous!
Bubble counters are not able to show how many individual bubble are going through it after about 6 bps but, I think they are still a valuable piece of kit as they do show every thing is working & it is still possible to get an indication of bubble speed!
Apparently there is an iphone app that works like a metronome & can counts the bubbles by recoding the sound they make while passing through the BC...

Thanks for the great replies guys. Much appreciated.