Common types of cloudy water are Green, White, and sometimes you can run into a Yellowish or brownish tint type of cloudy water. Green water is an algae bloom. White water is usually a bacterial bloom and the yellowish water is normally organic in nature.
The green water is an algae bloom.Free floating single celled algae is what is turning the water green.The cause is almost always, excess nutrients or excessive lighting. Algae consumes oxygen at night and a severe algae bloom can reduce oxygen to critically low levels, so while treating the tank, add aeration until you have the problem solved.The causes usually are Overfeeding, Infrequent filter changes and Infrequent water changes all of these things will cause an increase in nitrate and phosphate levels in your aquarium.Excessive light not only aquarium lighting but also might be intense room lighting or direct sunlight.
The solution is First eliminate the current algae bloom and secondly prevent it's return. Reduce feeding, You need to assure that all of the food is eaten Reduce light,Reduce the number of hours the tank lighting is on and make sure it's not getting direct sunlight. Increase filter maintenance and water changes to control nitrate and phosphate levels. Getting rid of the current algae bloom by covering the tank for 72 hours.During that time you can't allow any light source to enter the tank.Add lot of aeration to increase oxygen levels.

White cloudiness is usually the result of a bacteria bloom.Take a look at your ammonia levels. This could be a result of bacteria die off,you may experience increased ammonia and your tank maybe recycling.This could be caused by medical treatment of your aquarium that has destroyed the bacteria colonies, so always read labels before adding anything to your tank. As in algae, high nutrient levels can also trigger a bacteria bloom.Cleaning of all filters incorrectly, or the changing of the gravel can trigger a bacteria bloom, due to the removal of bacterial colonies that had settled on the filter media or substrate.To solve this control the nutrient level of the tank. Once you control this, the bacteria bloom will usually go away on it's own.