I am a new member and wanted to say Hi. I just got a Tobeco kayfun v4 and its leaking alot form the airholes, I have the diagram with the numbers to the parts and have been looking to replace the o-rings as mentioned in other posts. everywhere i go to buy o-rings have an outer diameter and inner diameter and thickness, does anyone know exactly what size i should get for #16 & #18 o-rings. the diagram says 11x1.5 and 10x1.5 but is that the inner or outer diameter. my tanks o-rings are way wider than that and a few i bought are either too thin or too thick and cant close it down completely. i would appreciate any help