On the advice from a friend on a different forum, I purchased a tank glass scraper called the flipper. This scraper is one of the best I have ever seen. it has a very low profile, and actually flips while in the tank to either a side with a steel blade or a scrubbing pad. this is done by just flipping the magnet polarity on the outside of the tank. I allowed the coraline to build up on my frag tank to check out it's ability. I must say it did a fairly good job, and with it's low profile I was able to get to corners and areas near the rocks that I have not been able to get to in the past. Cost $25.00 +/-.

Website: http://flippercleaner.com/

I am no way affiliated with this company, and stand to have no gain from this endorsement, I just want to share good items with fellow reefers to help in this hobby.