Ideally nitrates are going to be <5 but <20 is usually ok. Any more, though can be bad and is likely one reason why they aren't opening up fully.
Salinity should definitely be brought down immediately. 1.026 is the upper range of tolerable for most creatures we stock in aquariums, and is around where natural seawater is typically....but much research has been done on this issue and it is actually beneficial to keep the salinity lower in the 1.022-1.024 range.
An added benefit of this, as well, is that if your salinity is 1.023 let's say and something happens where you may not be able to care for the tank as promptly as you'd like, evaporation will take longer to raise the salinity to dangerous levels. If it is already at 1.026 evaporation can cause headaches pretty quickly.
Another reason would be the phosphates. The first course of action there would be to identify where the phosphates are coming from (are they in the water you're using, some food maybe? Leeching out of the rock? etc.).
Then you can take steps to correct that issue. Corals are generally not tolerant of phosphate levels.