55ppm CYA is no big deal at all. Mine usually runs in the 70-80ppm range, and I've always had crystal clear water, never a problem.

I've often heard that 30-40ppm of CYA is the conventional wisdom, but I can tell you for sure that twice that amount works just fine. I've been at the pool store and those guys have told me that they only have seen "chlorine lock" problems when the cya level is in the 150-200ppm range.