I'm trying to get an idea of pump size for a 15'x30'x54" Sharkline Matrix. I've found various gallons amounts for this size, from 12000 up to 15000. Worse case, at 15000 and 8 hour turnover, that's a little over 31gpm. My pump will be located close to the skimmer and return, so my research suggests a 1HP pump should have way more than enough capacity.
However, around these forums I see people with similar sized pools, if not the same exact pool, but they have a 2HP pump. I understand every install is different, but this seems like a really big difference. Am I missing something or do people have pumps that are way oversized?
Also, after some quick online shopping, I've noticed that 1HP pumps don't seem to come in variable-speed; 2-speed seems to be the best I can find. Am I wrong about this or is the VS efficiency gains for a 1HP just not worth the extra cost? Efficiency-wise, would I be better to go to a higher HP to get a VS pump instead of a 2-speed 1HP?