That’s a good start. Running the skimmer a little drier should help reduce nutrient export. I’d also make sure you’re not running GFO or any other phosphate-removing media. If you’re not, I’d give the increased feeding about a week and test again before jumping into phosphate dosing like Brightwell’s NeoPhos. Sometimes the bacteria and corals will soak up the extra nutrients before your test kit starts showing an increase. If phosphate is still unreadable after a week of heavier feeding, then I’d consider dosing a phosphate supplement slowly like NeoPhos. The key is to bring nutrients up gradually while keeping your alkalinity stable around 8 dKH.