Airstone skimmer separate valve for each airstone?

[inerratum]

Im converting my skimmer to use four 6" fine pore diffusers and am not sure if I should put an airflow meter and valve on each airstone or just have one that controls all four. If I just have one I dont need to drill anymore holes into my skimmer body but if its best to have individual control then I have no problem doing it. What do you guys think?

Thanks

 

[lemures-ex]

I think individual control would be best. If one airstone is better or worse then another then it would affect all of them if you had them on the same line. The air is going to take the path of least resistance for the most part and any airstones that require a little more pressure are going to put out very little air.