If the tank has only been running a week Id definitely take it easy on adding anything at the moment. Give it a couple months at least before any coral are introduced. Better to wait longer in most cases. I know its hard, especially when the LFS is telling you to add things. But check out the threads on new builds and see how long these guys that have been doing this for years are waiting. It will be better in the end, I promise.
And welcome to the forum!
Couple months before adding any corals
This tank is 4 months old
There is no reason to wait to add corals. Go easy ones first. But even sps can be added to a new tank if you know how to keep the water stable. Stability is the key
But salifert test kits or Hanna. Don't waste your time with API
You need nitrate, phosphate, alkalinity, calcium, magnesium
Test alk, nitrates, phosphates every 3 days
Write down results
Test calcium every 2 weeks
Magnesium every month
Also you need to add rodi fresh water to your tank to adjust for evaporation