This is a sweet light that I am using in my 2.5 gallon nano coral tank at work. I am happy with the quality and packaging and it was delivered in a timely manner. I like having the ability to adjust the intensity of the light itself and of the color saturation. For those owners that are having a problem identifying the color adjustments of the four settings, believe me, each of the four settings has a specific function. You can shine the light onto a piece of glass that is tilted so that you can see the reflected light. Two of the settings are subtle, controlling the red and green hues. Check it out...
I can't speak for longevity but I like this product a lot in the short run.

★★★★★ from AtypicalCollegeStudent on February 8, 2018

Great light with a lot of power!

I ordered the Asta 20 planted version for my new 10 gallon tank. I thought I could make it work even with the tank rim (the product info has been updated to say it works on rimless tank only). Well, no luck on that, without cutting some of the rim. I was planning to mount it to a very small shelf behind the tank, when i realized it would clip perfectly to my bookshelf.

The light comes with a flat 180° lens that spreads the light pretty far, and a domed 60° lens that makes it more of a spotlight. With the 180° lens, I was disappointed in the color rendering. My fish and plants appeared washed out. I tried the 60°, and that's perfect! Somehow the light is warmer and more natural with the smaller spread.

Several points:

-as others state, the dimmer switch is finicky. If you want to dim it, start on full blast and slowly dial down. Going from off to medium dim just doesn't happen- it goes from barely on to almost full blast.

-the freshwater version does NOT come with a remote. The images clearly state the box contents. I think some people are confused because the box insert shows a remote. I believe the remote only comes with the saltwater version, but they use the same flyer inside each box, making it seem the remote should be there.

-this light has enough power and spread with either lens to adequately light a 10 gallon tank. I've got medium light plants on one end of the tank, and I placed low light plants such as java fern on the opposite end of the tank. I could swivel the light to spread it out more and get what's Is estimate to be medium light through the whole tank, but I have it focused on one side. My betta enjoys having a shady area, and I love the shadows and varying light levels this creates.

I'm attaching some pictures of my betta in a rimless 5 gallon so you can see the great color of his fins and the plants. I'm also adding pics of the 10 gallon with light at full power, then slightly dimmed.

Great little light for the value! Arrived promptly and professionally packaged (with remote). This light is doing a terrific job illuminating a 5 gallon nano reef with various corals.
As some have mentioned, it can get hot but you can preprogram the settings by channel ~as another reviewer has instructed. See the review titled "Istructions for remote" by Joel on Nov 22, 2017.
Be warned that you cannot time this light to switch modes automatically, this is a manually functioning remote light...the remote is universal for other models also (wifi button) but for for this Asta 20 Marine it only switches channels (no wifi).
For the price, this is a bargain.

I'm using the blue Reef/coral version in my refugium to grow cheato algae in my nano Reef tank for several months now and so far it works great! I've never been able to grow good cheato and now I've been growing so much that I've been able to sell it to my local Reef store, I'm probably gonna order another for my other Reef tank, I use it at full power, it does get very hot when using it that high but it seems to be no issue, remote control is a nice feature

For the price tag I was a little hesitant to buy this light but after receiving - I am so glad I did. This light gives my tank a very natural look and my fish love it. I just got it and so far, I'm inpressed. Now I just gotta hope my plants like it too.