Ya... I used a Salifert Calcium test the other day and it told me my calcium levels were at around 800... I didn't believe it since I had no precipitant going on in the tank. Got a new test and it came out at 420. A good 25% WC won't do anything but good though...
If you do a water change use Instant Ocean it's low in Ca. You may want to have someone double check your levels too, sometimes Ca kits can be fickle, it has something to do with Mag IIRC.
I don't think your high Ca levels would affect your clowns