If you have green water, don't expect water changes to clear it. Sometimes it makes it worse, in my experience, and especially if there is ammonia in your tap water. The two things that worked for me are a UV sterilizer (The green killing machine) and SeaChem Purigin a filter medium. Black outs did not work for me.
Ya know, given the tap water ammonia, I wonder if Purigin or Zeolite would be your best bet to keep your ammonia in check. Both are filter mediums that many folks here don't like but I wonder if this would be an exception. The problem, in theory, is that both can stop working suddenly after a month or two or something like that and then you can have an ammonia spike. I've read lots on the Purigin and everyone seems to say they have never seen an ammonia spike. I don't know about Zeolite. Most will say you have to figure out why you have ammonia But, you have a special circumstance with the ammonia in the tap. Just a thought here.
Here is info on the green water. Your problem will be the introduction of ammonia with the water changes. This is from James Planted Tank website
http
/www.theplantedtank.co.uk/algae.htm
Green Water
Description This is a unicellular algae. Water goes cloudy. Sometimes just a green tint, other times it can look like pea soup.
Cause Ammonia is often the main cause green water. There may have been an ammonia spike that isn't detected with test kits. Other possible causes are an imbalance of nutrients and/or low CO2 levels.
Removal Large water changes do not seem to always help. If there is an imbalance in nutrients then fixing it will sometimes make it go away by itself after a while. A three day blackout followed by a large water change will hit it hard and sometimes may clear it. A UV steriliser/clarifier or diatom filter will clear it up very quickly and is often the only way to clear it.
A new method is to use freshly cut 1-2 year old willow branches about 0.5-1cm in width. Place these in your tank vertically so they go from the substrate to a few centimetres above the water's surface. After a few days they will start to grow roots and the green water should start to clear. When cleared remove the branches from the water.
Don't confuse this with a bacterial bloom which gives the water a white haze.