How to increase the font in Safari Reader on my iPhone 5S?

I'm visually impaired, and I require extremely large text in order to read at a relatively average rate. My iPhone 4S broke, so I bought the iPhone 5S. I was disappointed to find that Safari Reader no longer provides me with the option to increase the font once I pull up the article in a way that matches the font options on iBooks. I have already increased the text size to the largest possible font in Settings, but this isn't big enough. In fact, the text sizes are way smaller than what were on my old phone. My old phone gave me options that were almost on the verge of being obnoxious, and now I can barely see a difference between the smallest and largest fonts. Does anyone know how to make the font really big? By "really big" I mean as big as the largest font option in iBooks.

Try this… 1. Go to settings 2. Go to general 3.Go to text size 4. Make it as big as you want 5. Done… Enjoy.