Advanced LED Aquarium Light with Timer, 24/7 Lighting Cycle & DIY Mode, Full Spectrum Fish Tank Light for 24-30 in Planted Tank

hygger HG-978 Operating Instructions ("translated") I love this product. I got a smaller version for my 10G tank a year ago, and used that on my 20G"tall" tank as well. This larger one does more, and that's great! You have options. The bad news is, the instructions are somewhat difficult to understand. Like many things made in different parts of the world, sometimes the English instructions need some study to figure out what they really mean. It happens, and doesn't make it any less of a great product, IMO. So, after some study and experimentation, I was able to condense the basics of this light. There are three ways to use it. The first is to simply turn it on, select a color (it has a bunch), set the intensity level, and turn it off when you want to. Basically a "manual" light. One feature here... you can select a "Color Changing Loop" when you pick a color, and it will cycle through all the colors like one of those old Christmas tree back lights , if you remember those... Anyway... The second way to use it is to set a Timer. This light has a 6, 10, or 12 hour Timer setting. It will be "ON" for the selected amount of time from the time you set the Timer. There will be a 15-minute ramp up and ramp down in intensity at the beginning and end of the time selected. So, you select the color, the intensity, and the amount of "ON" time you want, starting NOW, and there it is. Using the light this way, I'd use a 12-hour cycle @ 75% intensity and shutting down about an hour or two after sunset, so I'd have to set the timer around 9AM this time of year to do that, and fiddle with it a few times a year to account for day length. Finally, there is a 24/7 preprogrammed setting. You have no control over the color or intensity or anything else other than figuring out the instructions! The instructions have to do with time. With this automatic setting, the goal is to have it finish at 22:30 or 10:30PM, according to the manual. Now, you only need to do this once... but what you need to do is look at the clock on the wall NOW, and select the starting point either closest to what your local time is right now, or one to "fool" the system into finishing earlier or later than 10:30. The time selections are 0800, 1000, 1200, 1500(3PM), 1800(6PM), and 2200(10PM). The idea is that if you are setting this light up and it's around noon, select the 1200 setting and it will now cycle without any further input. Off and into the night light at 10:30, and beginning the dawn routine at 8AM. That's it! I set mine at 0700 and selected the 8AM setting. The lights are running in night mode at 9:30PM rather than 10:30PM. So, you can offset or "fool" the system to shift the cycle around the clock a bit. A couple of things about this setting... It seems to never get brighter when you first set it up. VERY SLOW ramp-up and down. It actually takes an hour or so to ramp up to 100% intensity. Nice, really... but I thought it wasn't doing anything at first. And the same to ramp down. The only issue I may have with this setting is if I get too much green algae. That's my sign in my planted aquarium that there's too much light. There's no control on this setting other than time-shifting. I'd like to be able to set an upper limit on intensity. So, depending on my needs for the plants and balancing the algae issue, I may end up using the timer versus the 24/7 setting. That jury is still out. Excellent product! Now, if only someone made one exactly like this one only with a USB port and completely programmable! ::hint! hint!:: *********** After a week or so of using this light, I've settled on the timer function as my default. I set the timer to start at 9AM and go to 9PM. Because I am always up long before 9AM, the timer mode allows me to turn on the light earlier without disturbing the OFF time of 9PM. Also, before 9PM, I can step down the light so that when I turn it on at 7AM or whatever, it's pretty dim, and then I can go from there until feeding time an hour after lights on. More manual, but I'm a control freak, which I think you have to be a bit to keep fishy friends.

I’ve had this light set up for just a week. My plants are already doing better. Pros: It’s a very nice looking light. Slim profile, black aluminum outer body. The 24/7 feature is perfect if you have medium to low light plants. I love how it cycles like natural light from sunrise orange, to daylight bright, to finish with moonlight blue. Color is showing up in plants because of the full spectrum of color used in the light. Quite an improvement from the simple all white leds that came with the hood of my aquarium kit. I bought a glass top for my aquarium and set the light on top to avoid any water reaching it, although it is said to be water resistant, I just didn’t want to risk it. I love the look of the low profile light over the bulky, higher profile black hood. Cons: The directions that come with the light are a nightmare. The manufacturer could provide a YouTube link with a demonstration, because if you want to use anything other than the 24/7 feature, the directions are confusing. There is also no timer if you just wanted full light for a set number of hours, and not the cycling light of the 24/7 feature. Despite that, the quality of the light is very good, and for the price, which is about a third of the highly touted Fluval 3.0, I accept the minor inconveniences for the substantial savings. It’s only been a week, so I’m excited to see how my plants do over the next couple of months. I’ll be back to update. Because of the lack of timer, and the very confusing directions, I couldn’t give it a 5 star rating.

Great product, easy to use.

Bought this as an upgrade to my previous light because I bought some plants with a higher light requirement and wanted full spectrum. Now where to begin with the issues with this product. 1. Lights get significantly dimmer after 1 months of use even with a lid. 2. No customization option for light cycles, and the preprogrammed ones slowly drift off the intended schedule after a week or so. Not the biggest deal but annoying when part of the reason I bought it was that so I wouldn't have to manually control day night cycles myself. 3. It's just a bad light. Light barely reaches the bottom of my fairly shallow 25 gallon tank. Most of my plants are melting and looking more unhealthy than when I was using basic led lights. Only thing that has grown significantly is the algae in my tank. Very disappointed would have returned if my window didn't expire. Wanted to give it a full month to see if the plants would adapt, they did not and now I'm stuck with a non-functional rapidly dimming product. Just spend the extra money and get a fluval 3.0, I wish I had bought that first and hadn't wasted 70 bucks on a useless light.

The only brand I will buy pretty much. They work, and work well. The timer on this is great, and easy to set up. I've had this for a while now and no issues. The only thing, is if you have it really close to the water, and water continuously splashes up on it, the side arms will rust. That being said, you don't want your light really close to the water anyways, so most of the time it's not an issue. They are sturdy aquarium lights. The arms are extendable to a point, as noted in the description and overall just a well designed aquarium light that is quality and has good aesthetics.