Aquariums at Home may earn an affiliate commission when you buy through links on this site. See footer.

Are LED Lights Okay for Fish? Aquarium Owners Need to Read this

It’s hard to know when you need different lighting, if you just don’t know what dictates need. I would say if you have an older set of aquarium lights that are not LED, then it’s time to upgrade. But if you get LED lights, will they be alright for your tank? I get it, I understand you wouldn’t want to invest in new lighting if they aren’t going to work for you. So…


Are LED lights okay for fish?  Yes LED lights are okay for fish. LED lights are also okay for live plants in freshwater aquariums. Aquarium lighting should be turned on for approximately 8 to 12 hours per day. 


There you have it. LED lights are fine for aquarium fish. That’s great to hear right? Now, what LED lights are best for your set-up. There are some things you should consider when purchasing lights. I am going to try and cover the questions you might have and what I feel you should know so you can make the best choice. Let’s do this!


Are LED Lights Better for Aquariums?


In general, I feel the answer is yes, LED lights are definitely better for aquariums than incandescent or other types of lighting. But why? I am glad you asked.


My opinion is yes, LED lights are better for aquariums versus other types of lights. I am going to list why I think this and hopefully I can give you the info you need to make the best decision for you.

  1. They are affordable. LED lighting, whether for aquariums or other applications, have come down in price over the last couple years. Aquarium LED lighting is extremely affordable now. For instance these LED aquarium lights are a smoking good deal on Amazon.
  2. LED lights can be purchased in full spectrum. If you have full spectrum lighting then you can grow freshwater plants with great success. Even with full spectrum to my first point they are still very affordable. Check out these full spectrum LED lights on Amazon. If you don’t plan on having live plants in your tank that is fine, the coloring is still fantastic.
  3. The color spectrum is amazing with LED lights. Aquarium LED lights are now available in white and blue meaning in the daytime, you can have bright white lights and at night switch over to blue lighting which offers an amazing view and ambience.
  4. Fish don’t really require full spectrum lighting in my opinion. This means you could probably save a couple of dollars if you purchase straight white LED lights.
  5. Next up is the heat factor. LED lights typically don’t throw off any or much heat. Other types of lighting will throw heat which heats up the top portion of the tanks water. This is fine if your heater needs the extra help but what if the lights are increasing the tanks water more than it should be? You will stress the fish causing issues for them. This is not the nest option. Get LED’s.
  6. LED lights are energy efficient. LED lighting will take less power to run, which means your power bill won’t be affected very much by them. This is an excellent reason to get LED’s.
  7. The life-span of an LED light vs an incandescent is much greater. Different manufacturers will provide different hours their lights will last. So no sense trying to list them all here. What is important to know is that an LED light will outlast incandescent lighting by thousands of hours.


To me, these are all excellent reasons to own LED lighting for your tank. Let’s now look at some other popular questions that come up around this topic.


Do Fish Like LED Lights?


I don’t really think fish know the difference from one light to the next. What they will notice is the brightness and heat generated.


Some fish will not take very well to overly bright lights. If you find your fish are frozen in fear or trying to hide when the lights are on, then maybe your lights are too bright. Adjust the brightness and things should be better for the fish. You could always stock more plants in the tank as well, this provides some protection from the lights while still being out in the open water for the fish.


What Color Lights Are Best For Fish?


I don’t think the color matters as much as you might think. Do your best to replicate the sun’s light in the fish’s natural habitat and you’re doing well.


Something you should be aware of though is that fish do much better when there is some darkness every day. I say that because some hobbyists will turn the blue light on their tanks and leave that on all night. Overall, I don’t feel that is healthy for the fish in the long run. You risk stressing the fish which will inevitably lead to sickness.


It’s okay to have the blue light on in the evening for a bit but turn it off when it’s time to go to bed.


Is Blue Led Light Harmful to Fish?


We just touched on blue lighting above but is blue light harmful to your fish? Some fish might be hesitant to come out of hiding in full blown bright white lights but with the darker hue of blue lights they will come out so you can enjoy them.


I don’t feel blue lights are harmful to fish as long as you make sure to give the fish some total darkness every day. If you have bright white on for a long time, then blue on for a while you could potentially end up with more algae. But harmful to the fish? I don’t think so.


White or Blue Light for Aquarium?


If we are talking about aquarium lights in general, then an actinic light which is 10,000 kelvins and is a mix of the white and blue spectrum. This is a great combo for marine corals and freshwater plants.


As previously mentioned, fish don’t rely on bright lighting as much as live plants do for growth and survival. I would recommend again that you have white lights on during the day and if you must have blue LED lighting on at night please keep it to a minimum.


How Much Light do Tropical Fish Need?


Your goal should be to replicate the amount of light your fish would get if they were outside. Of course, there will be some light that hits your tank naturally because the room the aquarium is in is lit either from the sun outside or lights on in the house.


I shoot for anywhere between 8 and 12 hours a day. I try to turn the lights on at the same time every day. You could make it easier for yourself and set-up a timer that way you know the fish and plants are always getting consistent lighting.


What is the Best LED Aquarium Light?


Whether you want the best LED light for a marine tank or freshwater tank, it’s mostly up to you to decide which is best. I can point you in the right direction though.


  • What is the best led light for freshwater aquariums? For a freshwater tank with fish only, a basic LED aquarium light setup will be sufficient. Just make sure the lights will light up most of the tank so you can enjoy watching it.
  • If your freshwater tank has live plants, which I always recommend, then you will want an LED light that is touted to have full spectrum so the plants will thrive and grow. Live plants are such an important piece of the freshwater tank puzzle so make sure to get the proper lighting for them. The lights you choose should have wording on the package that they are good for growing live plants. I like these lights for a planted tank from Amazon.
  • This article is mostly for freshwater aquarium owners but if you happen to have a marine tank, make sure to select lighting that states good for marine tanks. Especially if you get into corals, you will need the right light spectrum for growth. For a marine tank I like these lights whether you want to grow corals or not.



There you have it fellow hobbyists. LED lights are okay for fish and make a tank that much more enjoyable. So go ahead and get yourself and your fish some new lights. Thanks for reading.

Relate Aquariums-at-Home Articles

Can I leave the Fish Tank Light On?

Do Aquarium Fish Need Darkness?