MOST of the types of algae that will come a'knockin are not the types that your tropheus want to "graze" on, and they'll be ignored. If you don't mind doing your share of cleaning for the other types, then this is a good idea, as they do love to have some snacks between meals. However, most of their diet will still have to be fed via pellet/flake, so if there isn't any algae it won't hurt anything, and it'll keep algae off of the plants you intend to grow, as most of the plants that'll grow in these water conditions are pretty slow growers, they'll be susceptible to algae moreso than others.
P.S. for the water conditions, good plants for your tank have been listed above, and as has been stated they don't NEED this much light, but if you provide it, they'll certainly grow well for you.
one specific plant as Vals go I would recommend is Dark Red Jungle Val. It grows pretty tall and thick, nice color, and I grew it in my Mbuna tank and they seemed to hate the taste of the stuff. Mowed down everything else, but always left this alone.