Marine Parameters

[Julie]

Good morning, I'm looking for a little input on my readings:

Aklalinity 7 dkh
Calcium 480ppm
Specific Gravity .25

I just topped up this morning with distilled as I like to keep it around .24.
Any thoughts on Alk and Calcium?  The tank is filled with coralline algae,  I clean my thermometer off every few days just to see the temp.  I'm experiencing some red algae, but I'm trying to keep it at max 82.
My load in terms of fish and inverts is quite low; but I have quite a bit of LPS/softies.
The tank is 9 months old.
Thanks.