Diffuser Position

[stevereade]

I bought a glass diffuser from Malaysia on ebay a month ago, it turned up today finally. I fitted it and moved it to the other side of my tank below the filter outlet today. My old ladder set up was on the side of the filter inlet before as it was ugly and you couldn't see it. Problem is where I have it below the filter outlet it still doesn't push the bubble stream round the tank as the outlet is a pipe comes out about 3 inches. Should I bring the diffuser away from the back further so its positioned in the current as supposed to coming up behind the outlet pipe. The bubbles do get pushed around the tank as there is a circular current running around the tank but its entering the weakest part of the current. Any suggestions would be much appreciated, other problem is if I bring it out further it will probably end up half way down the depth of my tank and then you have the ugly air line look.

 

[JoshuaA]

I position mine next to the siphon for my Fluval filter, I asked my LFS owner after buying the CO2 kit the best positioning. He showed me 3 of his larger set ups and described why he put it there in depth. Ideally you want to keep it where the water is calmest so that the bubbles take their time to rise to the surface thus increasing the potential amount of CO2 that may dissolve into the water. Next to the intake is quite calm in my tank however if I put it next to the output then the bubbles would quickly rise and hit the surface almost instantly. Finally it can't really go anywhere else due to the cable management in my tank being absolutely awful!

Remember the key is for the CO2 to dissolve into the water not to force it around the tank, the currents in the tank will spread the dissolved CO2 elsewhere.

 

[stevereade]