old brick patio preservation

momof2labs

I have a huge brick patio (and 2 long sidewalks) in my 49 yr old home. I have pressure washed it (trying to be gentle) but the algae is about to take over. I've tried WetItAndForgetIt, OxyiClean, Bleach (1-4 ratio), etc. I've noticed more cracks in the brick and mortar with each passing year. Should I seal it with clear masonry sealer?

I do my research but I'm overwhelmed by exactly what I should do to preserve my brick patio and sidewalk.

Thanks v.m.

Fairfax, VA