Depth of diffuser

[ocean mang]

I have my co2 diffuser in my sump about 5" below the surface of the water. Does it matter how deep it is for good co2 dissolve? My ph is 6.6 and my kh is 5. According to the chart this is a good level of co2. My bubble counter is at about 10 bubbles per second. Tank is 200 gallons. Thanks.

[linelogic]

Would a single diffuser be sufficient for a 200 gallon tank ?! I've generally seen people fork out the CO2 tubing to 2 or more diffusers for very large tanks like yours.
I my opinion , depth should not matter, as long as it's not very close to the surface, in which case a lot of CO2 might escape to the surface without being dissolved.

Prabhu