Is 6 Too Many For My 20SF ?

[YeA 20sF]

Well I have been planing a small sandbar trip with a few freinds for this Saturday. Originaly it was suppose to be 3 boats and 10 people. But now at the last minute basicaly 2 of the other boats will not be able to make it and I am left with possibly 6 passengers on my 20. Its a quick shot from Dinner Key Marine near Coconut Grove to Nixon beach off of Key Biscayne. Just wondering if thats too too much or if I shouldnt have any issue ???????