How much conduit goes into Optima?

[NorCalPatsFan]

My final task before delivery is to run a length of 3/4 flex from my GFCI to the tub.  How much flex should I allow for between the control box and the side of the tub.  Is there room to spool extra.  I will be using the bottom right side hole.  I am also wondering if there is a knockout on the panel where power will enter for strain releif.  Trying to decide if I should just wait for tub placement or get the run complete ahead of time.

[Mendocino101]

if you want to be a head run extra and trim the excess....or wait and cut to size.....

[Brewman]

You might not be able to run sealtite all the way from your shutoff to your spa and not violate code.  Flex conduit in a spa is limited to a total length of 6' if I recall.
You may want to consider running schedule 40 or 80 pvc to within a foot or two of your spa, then switch to your flex.  The rigid conduit will better protect your electric line.

There is a knockout on the bottom of the panel, where you'd attach a connector to secure your flex conduit.
If you are buying the conduit and wire, I'd allow 5 or 6 feet for inside the spa, just to be safe.  You will need to cut this back when you run in the wiring and conduit, but it beats running too short.  Or you can wait, till the spa is placed, and just measure.  
Brewman