I don't see how two bulbs are anywhere close to where the tank can't keep algae away. I ran 2-24W T5HO over my 29g and just managed the lighting period closely and only lightly added ferts and didn't have an issue. Are you dosing anything?
Anyway, I would get new bulbs first. You don't have to get the expensive ones in the pet store, you could just go to Lowe's/HD and get 65-6700 or 10000k bulbs. Some will say that they let there bulbs go long without replacement, but if it has been a while and you are having issues and the spectrum has started to slide you will affect plant growth quite a bit. It affected mine quite a bit. Bulb still worked fine, but the plants just slowly started to die.
Anyway, I would get new bulbs first. You don't have to get the expensive ones in the pet store, you could just go to Lowe's/HD and get 65-6700 or 10000k bulbs. Some will say that they let there bulbs go long without replacement, but if it has been a while and you are having issues and the spectrum has started to slide you will affect plant growth quite a bit. It affected mine quite a bit. Bulb still worked fine, but the plants just slowly started to die.