My fishtank of Death...

I have a 10-gal. tank that has been up for about 10 year now. This last
month, I have been having
major problems. Maybe someone can offer suggestions? The tank has an
udergravel filter and one of those
"auqua-mini" filters w/the foam and charcoal filter inserts. I started
getting real bad algae problems - not much on the
tank itself or on any items in the tank. Mostly it was in the filter. After
a week or two, the foam insert and charcoal bag
are totally green and full of green particulates of algae (not long stringy
kind). Also, my tank water was continuously cloudy.

Also, I have had live plants in the tank for a long time. They got too big,
so I removed most of then. I tried using one
of the "algae fix" solutions. Has not helped much. Also tried solution to
"clear" the water. Sometimes it worked after a few days and the take was
very clear.

During this time, I had a Cory and Pleco die, and I have an dwarf fog that
got some sort of disease- it's body became covered
in white bumps all over and it died.

I have been doing a water change/cleaning every week using a Python cleaner
hose.

Also, I have checked all my chemical values - Ph, Ammonia, nitrate, nitrite,
and they are all within tolerance.

So, how can I get my tank back to a healthy state?

Thanks