Getting rid of greenwater is easy in an aquarium. It is some gross stuff that can be found in any body of water.
Some of the things you may have with green water is string algae, murky water that may be yellow and your water may even be smelly. Now that is besides your normal fish smell.
You may experience new green water in your tank when you first set it up or it may have been fine running for a while and all of a sudden it may just come about. You will be shocked and say how do I get rid of it. Many times it is from a cyanobacteria algae bloom. This can be caused from to much food, light, or even from an increase in temperature. Some of these factors can stress your fish and possibly cause other problems which can cause disease and pathogens such as ick.
Clearing up green water in an aquarium is pretty easy with a UV sterilizer as it fixes many of the problems associated with murky smelly, cloudy water caused by algae blooms and cyanobacteria.
A JBJ Submariner UV Sterilizer or Clarifier can kill algae and other pathogens quickly. In a few days your tank can be crystal clear and things running smoothly. The way a UV Sterilizer such as the JBJ Submariner works is it radiates the cell structure of the algae and disease pathogens such as ick spores and kills them off. This fixes the problem as even it does not kill the cell or spores on the first pass through, it alters them so much they cannot reproduce and weakens them.
Make sure to get the appropriate JBJ Submariner for your size aquarium and your green water woes should be cured.
Remember to make sure your quartz sleeve stays clean and to replace your submariner UV bulb as well.
Make sure to try and figure out what caused the problems though.
One last note: these work great in Nano Cubes.
Other methods are using the black out method with means no light at all for many days. Downside of this is if you have expensive corals and such they may experience stress or death due to this method. This is why sterilization is a better method than the black out method for getting rid of green or red water.
Green water pictures and algea
Green water can grow where there is excess light and nutrients. Keeping a tank by the window encourages green water, but you could try moving your tank farther from a window, having the lights on less, or using lower wattage lamps. Also, if you grow plants in your tank they can out-compete the algae for nutrietns. All these solutions will take time, so if you want a quick fix, you can keep the aquarium in total darkness for about 5 days. However, the green water could quickly reappear unless the initial imbalance is addressed.