Surfing Waves

Would a fish be good for me?
5'9 155 lbs 17 y/o
I want a good board to go fast on and progress on somewhat mushy waves.

Fishes aren't for beginners - they're loose and wobbly unless you know what you're doing.
Some of the so-called 'super-fishes' (7'+ with a swallow tail) are okay for an improver board, but still not your best choice for a beginners board. Stick with your 7'6 mini-mal plan.

The only thing I can really get access to now is a 6'6. Should i just try to learn that?

No, wait until you can get a suitable board. Much better to spend a while getting the right board than spending ages in the water getting nowhere on the wrong board.

im 5'9 155 is 18 1/2 not wide enough for me?

egrijalva27 wrote:im 5'9 155 is 18 1/2 not wide enough for me?

Not if you are a beginner. You want something at least 20inches wide. As suggested, a 7ft6 minimal (probably 21 or 22 inches wide) is a much better board to learn on.

You dont jump straight to the high performance board. You need to start on a different board and then, once you have learnt what you need to learn, you can start moving toward a more high performance board.