Clogged PVC problem

[Douglas]

Over the past few months, my calcium level was a little higher than usual. This caused a problem with my return pump and plumbing, becoming clogged and reducing the flow from my return pump. Is it best just to replace the plumbing piece by piece? or is there a way to clean it? It's a hard calcium build up, so running a cloth or "pipe cleaner" through it, may not do the trick so easy. The tank is full stocked and running, and i would like to not really shut down and rebuild. I'm open for suggestions or ideas to help with this problem.