A question... is the tank clear plastic? If so, can you somehow cover it, to minimize the light that can get in? Light accelerates algae growth. If the tank is opaque, of course, this suggestion won't help.
Many algae secrete a chemical matrix which keeps chlorine and other things away from the cells, and helps algae adhere to things. I suspect it would keep quaternary ammonium compounds out, too. It can be very difficult to get rid of wall algae. Talk to pool owners.
I suggest really scrubbing your tank for a long time with a higher concentration of bleach, and leaving it soak for a while. If it's glass you can bake it in the oven at 250 F / 120C for an hour.
Thanks. Unfortunately, it's plastic. I'll just increase the frequency of cleaning it.