What is a good light for a planted nano tank?

This question comes up a lot and it can be hard to find the perfect solution. I will cover lighting options I have personally used, and had success with, as well as lighting options that were suggested in a thread from my local aquarium Facebook group. There are a few key aspects that will help you identify the proper light for your tank. Before you can identify these aspects fully, you must know what your goal is for the tank. Let’s start by figuring out your goal and then we can identify what aspects of a light are right for you.

Ask yourself:

What type of plants do I want to grow?

There are three general light categories that plants fall under: low, medium and high light.

Here are some examples:

If your goal is to grow low light plants, purchasing a light that is only capable of growing low light plants may not be the best option! Once you get your first taste of plant growth, you’re going to want more plants and faster growth! Using a light that is only capable of growing low light plants is not the ideal route because light is the “limiting factor” in plant growth. Not enough light can prevent your plants from reaching their full potential. However, too much light can stunt your plant growth and spark algae growth.

Plant growth can be stunted for some plants under super high light because they don’t like having an abundance of light shinning on their leaves. The abundance of light can prevent a plant from growing upwards and reaching for the light. Plants under super high light already have all the light they need delivered to their current depth in the tank and as a result they may stay right where they are. Also with super high light, algae can begin to grow. This doesn’t mean that lower lights can’t grow algae, it just means that the algae growth will happen at an accelerated rate if you are not careful with how you use your light.

There are a few steps you can take to prevent algae growth and make sure your plants receive the appropriate amount of light. First, you can have some fast growing plants in your tank. This will keep algae out by letting the fast growing plants out compete the algae for nutrients. Along with a few fast growing plants, you can always buffer the light intensity by adjusting the height that the light is from the surface of the water. With some lights, you may be able to dim them, however this doesn’t apply for every light. Another way to dial in the light for your tank is to adjust the amount of time the lights are kept on during the day. It’s very important to have a timer running for your lights on a planted tank. Plants need consistency and will grow more efficiently as a result. I used to run my lights for ten hours straight each day. After attending an aquascaping workshop presented by Dennerle, I learned that it is better to have a break in light. This break in light allows for two separate photoperiods from which the plants receive light and grow all while acting as a deterrent to algae growth! Two other ways to prevent algae would be to have a high flow of water through your tank, the movement of the water over the plants makes it hard for algae to settle onto the leaves. It’s also helpful to have about 80% of the substrate planted.

The one thing you can’t do after purchasing a weak light, is make it any brighter than the light already is. It’s much easier to adjust your high light than need to upgrade your low light in the future.

Next we will focus on your tank and its location:

How big is my tank?

What are we working with here?

We can have anything ranging from a small puddle to a 10-gallon tank and still get away with calling it a nano tank. It’s important to know the size of the tank so we can determine how big of a light will “fit” the tank. It may sound great to blast a one-gallon tank with a 23W (Watt) light, but it’s just not the best idea. This brings us to a short discussion on the power of the light and PAR.

The power of the light, represented by the unit Watts, will be the next step towards determining if you have the right light for your planted nano tank. Some people go by the two watts per gallon rule but I don’t think it’s a rule that can function by itself and here is why:

If you walk into a hardware store and pick up just any bulb off the shelf, it’s more than likely a “warm” bulb or a “cool” bulb. Warm means it gives off a more orange color and has a color temperature of 2000K – 3000K (Kelvins). Usually a warm bulb is used indoors or in living spaces. Cool means it has a color temperature of 3000K – 4000K and is more white in color. This color appears brighter to our eyes than the warm light and is used in places like a kitchen, bathroom or office. So the reason why I don’t think the watts per gallon rule can function on its own is because these bulbs (warm and cool) do not have the correct color temperature that we desire to grow plants with. This doesn’t mean they don’t have the potential to grow a beautiful planted tank but that involves a deeper discussion on wavelength and photosynthesis. However, when looking for a light, we want a “Daylight White” bulb. Daylight White is usually in the color temperature of 6000K – 7000k and is a very bright light. To put it simply, you really can’t go wrong with a Daylight White Bulb and they will give you a crystal clear view of your plants!

The image above should more properly state, “This is the one we want to use to grow plants”, as all of them can indeed grow plants.

With my experience I have been able to use a 23W Daylight White bulb on a 10-gallon tank and grow many different mosses extremely well along with Cryptocoryne species, Staurogyne Repens, Anubias, Bucephalandra and Dwarf Sagittaria. These are not the only plants the light is capable of growing, that list is just the plants that I have kept. So the 2 watts per gallon rule works in this case but not if I was using just any average light bulb!

That being said, the two watts per gallon rule should be used to CHECK if your light is in the ballpark of what you want for your nano tank. Keep in mind that more watts does not necessarily mean it’s better. I used a Dennerle 5W light on a 10-gallon tank and was able to grow some demanding plants with the light. I would personally err on the side of more watts per gallon than just two watts. As I mentioned before you can adjust the height at which the bulb is positioned above the tank and you can keep the light on for less time to prevent algae growth.

It is also important to note that the further a light is from the plants, the smaller amount of PAR the light is able to receive. PAR stands for Photosynthetically Active Radiation. When PAR is measured, it can tell us how much available light a plant at a certain depth is able to use from the light source. Light traveling through the water column of our planted tanks works against us when it comes to PAR. This is because of something called the Inverse Square Law. The Inverse Square Law states: The light intensity is inversely proportional to the distance squared. The key with that statement is the distance squared, if your tank is very deep, then it will be a bit more of a challenge to provide plants with the light they need!

I realize this section can be tricky to understand, don’t hesitate to contact me and I can further help you understand and choose the proper light for your tank!

Now for the location of the nano tank. If you plan to put it on a bookshelf or in some tight space, you need to be mindful of the heat that the light will produce. The lower the power of the light, the less heat it produces, thus if you are using a high powered light, you would need to make sure that you aren’t going to overheat your aquarium. The heat from your light doesn’t have enough surrounding air to transfer heat to which results in your tank having a temperature swing when the lights are on. All tanks do this to some extent but with more powerful lights, it’s important to be mindful of how quickly your water temperature can change.

Lastly we will talk about appearance:

Do I care how my light looks?

This is completely personal preference. If it is high on your priority list that the light must look sleek and hidden on your aquarium, then I hate to say it, but some of these options might not be for you. This doesn’t mean that all the options are an eye sore, but most of the budget lighting options don’t even begin to compare to the sleek design of an ADA LED. I personally prioritize what is happening inside my tank and then make sure that the outside of the tank isn’t going to be a hazard of any kind.

Alright! Now that we have an idea of what our tank will need, let’s look at some lights and some possible pros and cons for each!

Budget Lighting Options

Listed below with each of their Pros and Cons!

If you have any questions about any of these lights feel free to contact me!

Budget Lighting Options

LED floodlights are a great option for a planted nano tank. I have used the 10W version on a 5-gallon tank and a 10-gallon tank and have gotten great results with both setups. On youtube, “The king of DIY” recently shared that floodlights were competing with and out performing the Kessil Amazon Sun lights.

It’s important to make sure you are buying the right light when looking at floodlights. This is where the key words ‘Daylight White’ and the color temperature 6000K-7000K are important to look for. Also the rating of the light is important. You want a rating of IP66 or higher to protect from splashes, and evaporation from your fish tank. IP stands for Ingress Protection, and the the number indicates the level of protection, here is a link where you can read more on this: http://www.enclosurecompany.com/ip-ratings-explained.php

PROS:

It’s very affordable!

Comes in different power sizes 10W, 15W, 20W, 30W and so on… perfect for larger tanks as well and not just nano tanks.

It has great light distribution. The spread of the light easily covers the entire tank and doesn’t leave any corners of your tank in the dark!

Most of them come with a mounting bracket

Delivered right to your door! (The only sources for these lights that I am aware of is online)

CONS:

Most, but not all, require wiring a power supply cord. This is very easy to do and isn’t as scary as it may seem!

Finding a way to mount these lights can be a little bit tricky but not impossible! A few ways to mount them include making a DIY PVC stand, using a piece of wood and a shelf bracket or even using a gooseneck mount

It’s appearance isn’t great but not absolutely terrible either

Overall, this is a great bright light and would be suitable for heavily planted 3-gallon tanks to moderately planted 10-gallon tanks.

This light is great and can even grow red plants! The first picture is of my Scaper’s Tank right before I tore it down and changed it. The second picture shows some of the plants that it has now 🙂

I just planted 50+ cryptocoryne flamingo in this tank! If you’re interested in finding out more about how to prepare tissue culture plants, click here!

I’ve never used this light but I did notice that “Marks Shrimp Tanks” on YouTube has this light and didn’t seem to pleased with it.

PROS:

It has a clip that attaches to the side of the tank (I believe it only fits on a rimless tank)

It has an adjustable neck allowing for the light to be positioned according to where you want the light

It has the appearance that it belongs more on a fish tank than some of the other lighting options

There are two light settings allowing for a blue night light

CONS:

There is not indication on the color temperature of the LEDs used

Not the brightest, the 48 LED version is only 3Watts and without any information on the color temperature, it probably isn’t capable of very much

This light doesn’t allow for a progression towards higher light plants since it is on the low power side and doesn’t have very high output.

This would not be my first choice light but it may be good for a 1-2.5-gallon tank that doesn’t have demanding plants in it.

Another light that I haven’t used before but this one looks promising! It has 13Watts of power and is a “Full Spectrum” lamp. Full Spectrum is another buzzword like Daylight White indicating that it is capable of growing plants. I may be wrong, but I believe Full Spectrum and Daylight White may have slightly different meanings. In the description it says it’s recommended for 4-gallon to 8 gallon tanks.

PROS:

Sleek design that is ready to plug in, mount and enjoy!

It tilts and swivels allowing you to appropriately position the light

It’s a high output light

CONS:

The bracket!! We almost had a perfect budget light but the bracket only fits on tanks that have a 6mm or smaller edge.

Some amazon reviews reported having problems with the bulb life.

4-Pack

Clamp Reflector

Here is a clamp light and CFL bulb combination. This is a project tank and the algae is supposed to be there! If you’re interested in finding out why, you can subscribe to my youtube channel where I will be posting a video on the project!



This is another light that I have used and had success with. The light bulbs come in a pack of 4 and only cost about $10 for the pack! This light is a CFL (Compact Fluorescent Light) 23W T2 bulb that is equivalent to 100W output. It works with some desks lamps but it’s important that you follow the appropriate power ratings for the desk lamp that you have. I personally find it best to use a clamp light reflector for it.

PROS:

Very bright, high output

Affordable and long life (About 3 years)

Grows the heck out of most plants!

CONS:

The bulb and the lamp holding the bulb gets very hot!

Appearance can be a struggle with this one

Mounting it can be a bit tricky but with the clamp reflectors it’s possible to clamp to the side of the tank.

This light is great for almost any sized nano tank but isn’t quite enough for a 10-gallon tank.

Here is an old photo of growth that happened over just a few months using this light!

This peacock moss also grew in amazingly with this light!









Finnex Stingray

Finnex Stingray 24-inch

I have never used this light but have heard great things about it! The 24-inch version has 13 Watts of output and comes with (27) 7000K LEDs, (4) 660nm LEDs and (5) Actinic Blue LEDs. It says it’s rated for low light plants but could probably handle some medium light plants

PROS:

Fits nicely across the tank and is low profile

Perfect for low light plants

Provides a decent output of natural looking light

CONS:

Reported LED burnouts

Not suitable for higher light demanding plants in deeper tanks

Cost more than all the other options

UP Aqua LED Lights

https://buceplant.com/collections/aquarium-accessories/products/up-aqua-led-light-y-series?variant=20502877441

Buceplant $5 Coupon Code: http://rwrd.io/lzr4pko

I recently found this light in a small local fish store in my college town and almost got it but when I went back for it, it was gone! :O This one is definitely on my list to try for my 2.5-gallon tank that is sitting empty in my room. The light is designed for plants in a nano tank with a 7600K temperature rating and a 3W output. What’s neat about the light for sale on Buceplant.com’s website is the par data they have posted from when they tested on their Ultumn Nature Systems rimless tanks.

PROS:

Designed for plants

Sleek appearance

Recommended for nano tanks

Perfect for low light plants

CONS:

Rimless tanks only

Not suitable for high light plants

UPDATE: February 16, 2017

Reader Suggested Lights & Fixtures!



E27 LED PAR Lights

This light was brought to my attention on the Plantedtank.net forum and is a great light to use if you’re trying to crank up the growth on your plants. It comes in other light configurations instead of the Purple or “Full Spectrum” light listed above. I’m planning to get one of these bulbs and use it on my emersed setup since I’m lacking some light there.

PROS:

It’s a GROW light

Fit’s in a clamp reflector or desk lamp

Not terribly expensive, but keep in mind the price is for one bulb instead of the 4-pack CFL

CONS:

The above light gives of a purple glow

Would grow algae in a hurry if you don’t have the appropriate plant load

Safety Warning! I don’t remember where, but I read something about a potential hazard if you touch the light’s heatsink while it’s operating

This lamp is perfect! It allows for precise positioning of the light over your tank and is easily adjustable. I have used a similar lamp to this for my mixed shrimp tank and absolutely love it! If you’re picking up a pack of the CFL bulbs listed above, I would highly recommend you use a lamp like this!

No PROS and CONS needed for this lamp, the only requirement for it is that you have a ledge you can clamp the light to.

Buceplant Discount