complete novice needs advise

Hello group,

My son has a reef tank. The son has now moved away to college and has left
this mess for ole dad to care for.

I don't believe it is set up right because he has fought algae (slimy,
hair-like and green) since shortly after he initialized the tank. His buddy,
"the expert" moved away shortly after he bought the live rock but before he
introduced the reef creatures into the tank.

Here's the layout, the best I can describe it. A 10 gallon tank above a 35
gallon tank. The smaller tank has been divided into two separate
compartments by siliconed glass at a 45 degree angle from one side to the
back and to within an inch or so from the tank's top. As water is pumped in
from the larger tank it goes into the smaller compartment and then overflows
into the larger compartment and from there is gravity feed back into the
larger tank below. The smaller compartment has nothing in it but the larger
compartment has approx five inches of sand in it along with a strong stand
of calpera (calpura?). I am not sure that I am either saying or spelling it
right but I was with him when he bought it and I think that is what they
called it. There are two pumps in the large tank one to pump the water up to
the smaller tank and another to circulate the water. All of the lights are
less than 6 months old.

He has a rather large brain coral (approx 3x5 inches) and 3 (once was seven)
other smaller ones that I an not sure what they are called. He also has one
fish that is doing quite well, it is black and white and likes sleeping on
the brain coral.

The moss is terrible. I just changed out five gallons of the tank with
filtered water that was properly salted and warmed to tank temperature. I
then took out each rock and picked away the moss before re-entering them
into the tank. It is clearing quickly and looks much better. The coral
didn't look too happy at first but they quickly came out of there unhappy
looking state.

How many hours, at minimum, do the lights have to be on? The lights in the
big tank are on about 8 hours per day and in the smaller tank about 12 hours
per day. The large tank has a protein skimmer that is running (not sure if
it is properly working and set right), and there is a recalculating charcoal
filter in the smaller tank. The skimmer needs to be re-primed every couple
of days or so.

I have never understood the purpose of the sand in the smaller tank. It
would seem that if the water were pumped under the sand, as it rose through
it to the discharge line into the larger tank, it would be filtered. How can
the sand be expected to filter anything as the water simply flows over it?

How quickly should the trace minerals be put into the tank after a partial
water change? I was told to give them half a cap full of each of the
minerals once per week. Also, does the recalculating charcoal filter in the
smaller tank rob the minerals that I put in to feed the coral? With a total
of 45 gallons how much water should be exchanged when changing the water?

I hate not researching something before going for help in a newsgroup first
but I don't really have the necessary time to learn on my own and I am not
too sure that the reef creatures can survive if I don't do something
quickly.

Any help would greatly be appreciated.

jw