hidng fish, my stats

Ok, well I seem to have my algae problem under control. Now I have
crystal clear water in at least one of my ponds! Yippie! Well, sort of
yippie! Despite the clear water, I cannot see my sarassus comet or
butterfly koi because they are hiding. Constatntly hiding. The first
day we brought the two fishes home, they were swimming to an fro
ravaging me hyacinth and generally quite entertaining. The next
morning, my wife and I sat outside for the better part of the early
morning hours just watching them swim around. Later that day they
seemed to settle down. They werent swimming around or moving much. I
thought , well, theyre just not very active this time of day. Well, its
been almost a week and they have barely moved at all in the past 6-7
days. They keep hiding out by flower pots and under whatever they can
find. They wont move at all. My sarassus has been in the same spot all
day long. They will move around if disturbed, quite quickly too- right
back to where they were hiding. They seem ok physically, they look ok
physically, best I can tell. They just will not eat AT ALL and they
just lay motionless on the bottom of the pond, hiding. I have tested my
water: 1200 gallon pond -No Ammonia, no nitrites nor nitrAtes, PH(after
a 10% water change) is ~ 7.5-8. GH is at 75ppm and KH is at 40ppm, low
i know. I have bought some baking soda to attempt to stabalize/raise
PH#. As far as I can tell, other than the PH and KH everything seems
fine. What could be causing this lethargy in my poor fish? Also, how
much baking soda should I add to raise the KH from 40 to say, 120? I
used a formula I found elsewhere on the forum [ (1200*80)/5000=19.2oz
of baking soda to raise it from 40 to 120. ]How much should I add at
one time? All of it or about 1/4 of what I need over a period of 4
days? Should my GH be tampered with? Should I ask another question? Is
wrestling fixed? If a tree falls in the woods....