I think so

But make it at least 3 times a week, not 2. Do you have enough algae in your tank for the BN pleco to graze on during the rest of the 4 days a week? If you have completely no algae in your tank, I think you should feed more often than 3 times a week. Carol (Butterfly) has BN plecos, so she would have probably the best answer for you.
Have you ever tried feeding your BN pleco with a zucchini slice or a spinach leaf? If not, try it. Algae eaters love to eat zucchini and spinach too

You'd be greatly enriching your BN pleco's diet by adding zucchini and spinach to it. How about algae wafers for 2 - 3 days, zucchini slice for 1 day, and a spinach leaf for 1 day?
If you don't have veggie clips, you can buy one at your local fish store. You attach zucchini or spinach to the veggie clip, and you attach the clip to your tank wall. This way, the food stays in one place instead of floating around the tank. The uneaten leftovers of zucchini and spinach should be removed from the tank after 24 hours.