Well 520 is too high!!!
Your alk is good... what is the size of your tank... If you are adding anything on your calcium side you have to stop it. What are you using to add ALK? if you dont then you should think of something to balance it.
It can be the two part or anthing that will add alk.
I use B-Ionic. There are other alternatives...
You can also look for Baking Soda - Arm & Hammer - Unscented (Raises Alkalinity)
And on the calcium side... you have just to wait till it goes down.
If your ALK is 4 then the balance for the calcium is 440.