Don't add the Fiber Clear. I don't know what that is and you don't anything else that might contribute to the problem. Instead, try adding some DE to your sand filter like many of us do. It may help. Read more about it at the following link. Be aware that you may not see the rise in pressure immediately. It usually takes about a half hour in my pool to see it. So, don't add too much DE. If you overshoot, backwash it out and try again.

http://www.poolforum.com/pf2/showthread.php?t=3742

The pump size sounds reasonable to me but one of the equipment gurus will hopefully chime in if they see a problem with your setup.

Keep up the frequent testing and adding bleach. I know it is a pain, but eventually your pool is going to be fun and not so much work!

Also, do me a favor. In your signature, please put that you have a Taylor K-2006. We help so many people in so many threads that it gets time consuming to have to scroll back over and over to look to see who has what. That will be a big help and a time-saver if you can do that.