A tank with less phosphate will certainly help. This can accomplished by lots of water change, reduce feeding and less light.
Seachem Phosguard in your filter will help, along with the addition of a few SAE's ( Crossocheilus siamensis). The Siamese algae eater must not be confused with the Chinese algae eater or the Flying Fox, neither of which will eat BBA. I also agree cutting back on the duration of light and newer bulbs will also help somewhat. As for cyanobacteria tetracycline will kill it.
You will be surprised how quickly SAE's will eat the BBA, provided you're not keeping anything that will eat them first.
Phosgaurd will remove all of the phosphate which will kill the plants. Dead plants will leach nutrients back into our the water, exacerbating the algae problem.
Dieboldly
, all of the above suggestions are decent ones, with the exception of phosphate removal in my most humble of opinions. I think that most of them are unfortunately a band aid solution. A few questions:
1 are you running co2?
2 why is your temperature so high?
3 when did the problem begin?
In planted tanks, unstable or low co2 will induce black beard algae very quickly. The problem is usually too much light, as addressed above. Light drives nutrient intake. The more light, the faster the intake of nutrients. If your co2 can't keep up, it creates an imbalance that allows algae to thrive. Many forms of algae also thrive in low oxygen environments. With a temp of 85, your water contains less oxygen than water at a lower temperature potentially adding to the algae problem.
To get the algea gone, dose with seachem excell. Double whatever the instructions say for your size tank. Spot treat with hydrogen peroxide. I usually get a small syringe, turn off all pumps and filters, squirt the peroxide directly on the algae covered areas. Dose no more than 1ml per gallon. You will see the peroxide starting to make a ton of bubbles. That's how you know it's working. Dose once daily for about a week. The algae will start to turn reddish, or grey depending on exactly what type it is, then eventually just go away. Also, lower your temp to 78, and decrease your lighting as said above. You may have to end up raising your lights higher to keep the algae away. That or start injecting co2.