Answer: Yes, it is difficult.
Explanation: Yes, it can be challenging to lower the calcium hardness in a swimming pool if it becomes too high. The primary method for reducing calcium hardness is through dilution, which involves partially draining the pool and refilling it with fresh water. Additionally, using a calcium remover chemical can help, but it's essential to follow manufacturer instructions carefully. Regular testing and maintenance can help prevent calcium buildup from becoming a significant issue.