The hopper has at least 4 different slopes. The one you are referring to is the transition slope from the shallow end which on an 8' deep pool is usually 13 or 14' long - you are correct that you either loose some shallow end or steepen the slope if you go with a 10' bottom However, another alternative is to add an extra 4' wall panel to the sides (instead of having an 18X 36' pool you get an 18X 40' pool) If you go with the 10' deep end, you'll have to custom order the liner anyway so the only extra expense is the 2 4' panels

The other slopes are from the side and back walls - the biggest problem is being able to apply the pool base to them at that height - 8' walls are a royal PITA - I shudder to think how bad 10' walls would be - you'd probably have to set up some scaffolding If you don't have someone experienced with doing the walls - 8' is ~ out of possibility and 10' should not even be considered

I'm not trying to discourage you from building your dream pool, just give my honest assessment.

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