KH and ALK going down

[wetone]

My KH and ALK seem to be heading down lately, I add Kent ProBuffer and it brings it back up but goes down again. I have a 75g with a 35g sump, 125lbs LR and lots of LPS and soft coral, shrooms and more. I slowly am adding more stuff to the tank. Is this decline a natural occurance, and I will always be adding the boost??
My DKH is about 9.15, ALK 3.25, PH is 8.0-8.1, and Cal 480.
I constsntly add kalk via a drip for evaporation.
Any thoughts??

 

[q]

What have you been adding?
Might want to let the tank sit for a while so things can stabilize

 

[wetone]

I add Kent Kalk as a top off for evaporation and I add about 1 tbl of Iodine every week...thats it...ALL in tank is awesome with polyps and corals growing and I frag some things and they are growing too.
I just started adding the Kent Probuffer once every 3 days since I noticed the DKH level low ( I didn't notice anything wrong, just was doing a full set of tests that were about 6 weeks overdue....too many leaves to rake in New England !!)
I also do a 10-15G water change every 3-4 weeks....

 

[wamp]

Do you add Kalk during the day?

 

[q]

As the load of corals increases so will the amount you need to add. Both calcium and alk.
You may not be able to keep up with just kalk. You could spike it with white vinigar which will increase the amount the kalk is able to disolve making it stronger. Or by using other additives to help boost it.
If you want to add white vinigar I can give you directions but as I am not doing it yet I will have to read up a bit to explain it in any detail.
If you add iodine you might want to test for it as it can get to toxic levels. Just checking don't want to nag.