Hey Reyma,
It sounds like there are a couple different issues causing your algae.
The first being your source water. Like Jacobs already stated, tap contains a lot of undesirable organics and metals. Even if you are treating it for chloramines, the rest is still there. The water vending machines will work, as I'm still using them, unfortunately, but the best way to go is a RO/DI unit. If purchasing a unit, make sure that it is RO/DI, not just RO. RO water will still have TDS (total dissolved solids), the DI (deionization) unit is what makes it pure water.
The other issue could be your lights. The Kelvin rating of the bulbs is important. Kelvin measures the color temperature of the bulb, if the bulb is 5700-6500k, this will aid in the production of algae. Most people who have planted tanks, I believe, run around 5700k bulbs for this purpose. You want a bulb rating 10,000k or above. For most people too, this color temperature is more pleasing to look at, not so yellow, more bluish/white.
Another reason a lot of people get algae problems, is over feeding in combination with not enough water changes. This builds up organics, which feed the algae. There are some good articles on this site, about how to deal with Cyanobacteria. Check these out, as they will explain it all. Reducing your photoperiod will help to get it under control, but is in no way a cure.
Sorry for the mini-novella of a post, but I hope this helps you get it under control.