scrub them with a toothbrush then do a water change.
then do weekly changes 10-20% and feed less. Anything that is left on the bottom after the first couple minutes is simply waste food, and will only feed more algae. You can cut the lights off for 2 days, then put them back on for 4-6hours a day while your doing your water changing period. Ill bet within a month your tank will be clear.
Then its a matter of preventative maintenance.
1. Clean the glass daily. seriously, it only takes 5 min.
2. wipe problem algae away right before you do your water changes from now on, a toothbrush is super handy at this stage, or a larger dish scrubbing brush(use a brand new one).
3. Use your siphon/pump in the midst of the densest part of the algae cloud the appears.
4. Feed less, your algae wont grow as fast if its not being provide with nutrients that come from over feeding. Its doing its job, keeping pollution down. And to speed things up reduce lighting till the problem is gone.
Two tips:
A GFO/Carbon reactor. Cheap to setup, and keep running(about a 100dollar investment gets you reactor,media, and pump). Great for people who want the crystal clear pristine water. Keywords to google are "bulk reef supply"
Also read up on turf scrubbers. I am running mine in a skimmer less system. And The only time I ever get faint readings of trites/trates is when I clean the scrubber and it needs a couple days to catch up.
