Decided to invest in a Eheim UV sterilizer to get rid of my green water problem... been doing 20% water changes almost daily or every 2 days for the past 3 weeks... My 3ft tank is in the balcony so it does get a fair amount of light even though i put all the blinds down...

Questions:
1. Is the Eheim Reeflex 500 enough for my 3ft tank?
2. Can this be place horizontally instead of vertically? If place horizontally, will the mounting bracket hold?
3. How should i connect it? To the outflow of my cannister filter or outflow of my chiller?
4. Do i need to reduce the flow rate to use the UV sterilizer? I am currently running a Eheim 2075 filter and teco 500 chiller.
5. When should i turn on the sterilizer (day or night) and for how long?

Thanks.