Sounds like things are improving. One thing to keep in mind is that it's easy to get caught up in chasing the "perfect" parameters. However, most tanks, given good,consistent husbandry (feeding, water changes, flow and lighting) will balance out to a healthy point by themselves. For example, many healthy reef tanks can run relatively low on PH while the corals thrive. The tendency to constantly tweak a system with additives, new equipment etc... has a destabilizing effect overall and corals love stability. If you change anything about a corals care you should really give it at least a month to gauge the reaction. People who change things in their systems or their maintenance routines often, never really get to see what worked or didn't before rushing on the next quick fix. They will never know that they got it "right" many times!
What I would advise is that you continue to allow the tank to settle down to its own balance. Large frequent water changes with good quality water, keeping the skimmer clean (big fun!) and maybe weekly use of high grade carbon. Use the test kits to understand the baseline, healthy status of YOUR tank instead of going out and buying something to make your tank fit an idealized model.
