Hi, I am new to the pools and new to this forum. We recently moved to a house with a outdoor inground pool in Southern California. As we are moving, we haven't paid attention to the pool until 5 days ago I noticed mustard algae on the pool walls. I used the Taylor test kit, and in the FC test the sample didn't change any color, i supposed that there is no FC in the pool. The ph was fine. But, when I did the CYA test the read was way above 100! There was not a number I could read. We are now thinking about the partial drain and refill the pool but after reading the feeds here we are afraid about the potential cost if there will be a destruction. Is there any other way that we can deal with this? The heat will hit us during the coming weekend.