Review on Hygger Advanced 24/7 Lighting Cycle LED Aquarium Light with Full Spectrum, 6 Colors and 5 Intensity Settings - Customizable Fish Tank Light for 30-36 inch Freshwater Planted Tank with Timer by Joe Daniels

hygger HG-978 manual ("translation") I like this product. A year ago I bought a smaller version for my 10GB tank and also used it for my 'big' 20GB tank. This bigger one can do more which is great! You have options. The bad news is that the instructions are a bit difficult to understand. Like many things made in different parts of the world, English instructions sometimes require some study to understand what they really mean. It happens, and that doesn't make it any less of a great product in my opinion. So, after some study and experimentation, I was able to summarize the basics of this lamp. There are three ways to use it. The first is to just turn it on, pick a color (it has a lot), set the intensity level, and turn it off whenever you like. Basically "manual" light. A feature here. You can select "Color Cycle" when you select a color and it will cycle through all the colors like one of those old Christmas tree lights if you remember it. In any case. The second way to use it is to set a timer. This light has a 6, 10 or 12 hour timer setting. From the time the timer is set, it will stay on for the selected amount of time. At the beginning and end of the selected time, the intensity will increase and decrease for 15 minutes. So you choose the color, the intensity and the "ON" time you want, starting NOW and that's it. If I was using light this way I would use a 12 hour cycle at 75% intensity and turn off about an hour or two after sunset, so at this time of year I would have to set a timer at 9am to do this, and messing around with it several times a year to account for the length of the day. Finally, there is a pre-programmed 24/7 setting. You can't control the color or intensity or anything else other than figuring out the directions! Instructions refer to time. With this automatic setting, the goal, according to the manual, is to be ready by 10:30 or 10:30 p.m. Now you just have to do this one more time. What you need to do, however, is NOW look at the clock on the wall and choose a starting point that is either closest to your local time or one that "tricks" the system into making it before or after 10:30 clock ends. Possible time options are: 08:00, 10:00, 12:00, 15:00 (15:00), 18:00 (18:00) and 22:00 (22:00). The idea is that if you set this light and it's around noon, you select the 1200 setting and it will cycle through now with no further action. At 10:30 the night light is turned off and on and at 8:00 the morning routine begins. That's all! I set mine to 07:00 and chose the 8:00 setting. The light works in night mode at 9:30pm instead of 10:30pm. This is how you can compensate or "cheat” the system to shift the cycle a little around the clock. A few words about this attitude. It never seems to get brighter when you first set it up. VERY SLOWLY rises and falls. It actually takes about an hour to get the intensity up to 100%. Nice really. but at first I thought it was useless. And the same for the decline. The only problem I might have with this setup is if I get too much green algae. This is my clue that there is too much light in a planted tank. There is no control over this setting other than the time offset. I would like to be able to set an upper limit for the intensity. Depending on the needs of my plants and balancing the algae problem, I may use a timer instead of a 24/7 setting. That jury is still out. Good product! If only someone could make the exact same thing, only USB connected and fully programmable! ::A notice! Note!::**************** After about a week of using this light I decided to go with the standard timer feature. I set a timer for 9am to 9pm. Since I always get up well before 9am, the timer mode allows me to turn on the lights earlier without disrupting the 9pm time-out. Also, I can dim the lights until 9pm so if I turn it on at 7am or whatever it's pretty dark, and then I can move on to feeding time an hour after turning the lights on. Rather tame but I'm a control freak and I think one should remain a little suspicious of friends.