ok ive decided to get a uv. after reseaching a bit i found that a pond clear advantage 25 watt is what is needed as well as what i am going to order the 1st.Iknow someone told me to use 40 watts. I feel that i dont need this much wattage,as the tank will never be saltwater. as far as algea clear i will never use it again down one more fish...and it was the flower horn.