That's awesome! I'll be doing the same thing next weekend. My 16' intex arrives tomorrow. Im a total rookie at this, so i've been debating between a intex filter and pump or another brand such as the haywards.levelled the ground with the tiller as step #1. planning to rent a Vibratory Plate Compactor on weekend and be ready to put FOAMULAR 150 foam (1/2" or 1" .. not decided yet which one) liner then.
The good thing with the tiller + clay gound: tiller brakes ground into small pieces so, watering slightly in the evening and using compactor in the morning, will do a solid base for placing foam on top. The bad thing - not exact levelling BUT very close to what is needed )))). Hope foam plates will do the rest for better levelling. Decided not to go with sand on top of the clay. Spent around 5 hours on this exercise.
First picture - where I ended on the second day, the second one - not-finished-yet job.
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