How do I have a brightly-lit tank without algae?

First off, I think that is ALOT of light for that tank.

I know, but the whole point of the tank is for it to be seen, and with
less light, it just doesn't show up. With the higher light, it looks
stunning.

Anyway, I would have thought this was fairly low compared with the
African sunshine, no? I don't know how that rates in wattage, but I can
look directly at the lights above my tank, I can't do that to the sun
here in England, so the African sun would be way brighter.

If you must keep all
that light then shorten the photo period (only put the lights on at night
while you are home, no need for them to be on all day long.

Problem there is that the tank is in a room that is occupied most of the
day. Ideally we would like the lights on all day long as the room is
used from about 7:30am pretty much non-stop until about 11pm. We have
compromised and cut the photo period back to about 2pm to 10pm.

Try to angle the
lights so they are shining toward the back of the tank and not onto the
front glass.

Already done that. The halogens were pointed more at the middle and back
of the tank. I just changes them for some less directional lights, but
they are still over the middle of the tank.

Really no need for all that light on a Malawi setup, unless
you're growing marijuana at the base of the tank HTH

I didn't know it grew under water!! Not that I want doped fish... unless
it might calm them down a bit!! I could do with getting Biffer to mellow
out a bit, he's always chasing the other fish around. Beautiful fish,
but a bully.

Thanks for the reply.

--
Alan Silver
(anything added below this line is nothing to do with me)