Some good info there. When the pump room is below the water line in most cases, if not to much, then normally the 3 piece ball valves should be placed above the waterline! See pictures for 8 valves we replaced and increased height to above waterline.
1 hp pump for a 90, k litre pool is a joke. You where wise to upgrade to 1.5. Depending on the size of the filter, even 2hp would have been good.