I have a 32 oz standard dubro tank angled in the back of my kingcat right on the CG for Smoke. It slides right in.

I have the 16oz center tank between the kevlar. It holds 4 liters or something like that. I saw no harm in keeping the 16 oz tank in place for insurance in case I ever cavitated a side tank and they quit feeding. Yes it weighs one pound more but... the thing hauls absolute bootie with a Wren 120 on it that was turned down to 25lb. we radared it at 195-200 several times. the huge wing and it still slows down with the extra weight.

So my opinion... keep the 16oz center tank, put a 32oz or so smoke tank, and fly your butt off... Another reason I like the extra fuel: I take off first and land last during multiship gaggles.... Thats worth it.. if someone has an issue: I can sit up there and hold for 20min if I have to..

gives me alot of options...

Love the JET!! Still getting used to it, but its sure a sweetie to fly..