Aquarium Lighting Guide; including bulbs and light timers

In order to answer more and more questions of Aqua-Fish.Net’s visitors, this guide is devoted to information about aquarium lighting, bulbs, fixtures and timers. All questions have been compiled from previous statistics. If you’re looking for answer that isn’t answered here (or on this website), feel free to leave your question at the bottom of this page and we'll answer it.

Which lighting is suitable (best) for a freshwater aquarium?

For plants I recommend AquaGlo bulbs (I have had very good experience with these). In past I recommended 0.625 Watt per 1 litre for very fast growth. However, nowadays I am using 0.308 Watt per 1 litre. It is enough to grow plants such as Vallisneria Gigantea, Vallisneria Spiralis, Anubias Nana. Some plants (especially the floating ones) can do better under ordinary sunlight than under special aquarium lighting. Pistia Stratiotes is a nice example of such a plant.

Never buy bulbs which heat the tank too much. In Summer this can cause serious overheating.

How long should an aquarium light bulb be?

If the fish tank is 100cm long, I recommend to use a 90 cm long bulb (or less, but not less than 70cm). Always try to fit the length as much as possible. If you cannot buy say a 120cm light, then combine two 50cm for instance. Each aquarium light hood should mirror emitted light back to the water (a simple aluminum foil can be used) in order to maximise the efficiency.

What is lux?

Lux is the unit of illuminance. Freshwater aquarium plants need maximum 5 000 lux and salt water plants, sea-flowers and corals need more than 6 000 lux. (aqua-fish.net/articles/aquarium-lighting-guide-answers-pictures)

How much light do fish need and do they need light?

In terms of additional aquarium lighting systems, fish do not need any light at all as long as there's enough sunlight in the room. The only thing which needs light are plants. However, light helps fish to find food and to orientate. As I mentioned above, 0.308 Watt per litre is sufficient for fishes. Even 0.15 Watt per litre would do well.

Bear in mind that fish may be scared of light especially in two cases; When the light turns on, and when the light turns off. This is the reason why I recommend to turn on and turn off the lights when the room isn’t in dark.

How many hours should be a fish tank lighting turned per day?

I recommend between 10 and 12 hours. Sometimes it’s OK to turn on the light bulbs for only 7-8 hours, especially during Winter. During Summer feel free to lengthen this period to 14 hours.

Do I need an aquarium light timer?

Although it is not necessary, there are unspeakable advantages of an aquarium light timer being used along with bulbs; It helps to simulate the day-night cycle perfectly, timers save energy, when you’re on a vacation it works automatically and gives the light to the plants in your fish tank. I use timers on all my tanks. An electronic one costs only $10 and it is possible to connect as many cables as needed to one timer.

Which aquarium plants have low requirements on light?

There are quite enough of them, our database contains these:

Should I use night aquarium lighting, and what is the purpose?

Many aquarists use a 12V lights taken from computers for this purpose. Actually, such a moonlight is a great addition to every aquarium because fish are able to orientate better. I recommend this to every fish keeper because even my fish lost eyes, or hurt themselves very badly when they chased each other in night.

Night lights are, however, usually used in reef tanks. If you’re interested in buying one, here is the link.

How to create a fixture for aquarium light bulbs?

There is an article devoted to this topic already: aqua-fish.net/articles/diy-aquarium-light-fixture . About canopies there are more articles, they’re available here:

What is a T5 aquarium lighting?

According to this guide: aqua-fish.net/articles/details-t5-aquarium-lights , a T5 bulb can be characterised as: The five in T5 applies to something as innocent as the diameter of the tube. Five eighth of an inch (62mm) to be exact. Many people are unaware of this fact, yet when you think of it logically, the same scale carries its way through all of the dimensions of aquarium lighting tubes, up to and including the T8 which is exactly one inch (100mm) in diameter.

Related question:

What is a T8 or T12 aquarium lighting? See the explanation above, please. The difference is in the diameter.

How and where can I buy cheap aquarium lighting?

As I mentioned my previous articles, “cheap” usually means getting a discount. Let me explain... I use to buy fish food, filters (from time to time) and other aquarium accessories in one aquatic shop. Thanks to this fact I know the seller very well and if I ask for a discount, I usually get it. Sometimes it helps me to save between 10% and 20% depending on the item’s price. Naturally, when I am buying food for $3 or $4 only, there is no reason to ask for a discount. If you want to buy some lights online, then this link should help you to find what you need.

What is a underwater aquarium light and where can I buy one?

There are more types of such lights on the market including halogen bulbs and LED lights (LED aquarium lighting is now widely available as a replacement of T5 or other types of bulbs). In general, this kind of lighting isn’t suitable for small aquariums as it needs some space. Depending on the spectrum, the water can be coloured to colours such as yellow, or purple, or more. I wouldn’t ad underwater lights to small and shallow fish tanks, and so shouldn’t anyone (the effect will be minimised). I found this web page where you can buy underwater lights:

petco.com/product/8284/Miracle-Beam-Hi-Lite-Underwater-Aquarium-Lighting-System.aspx

The link above worked on 31/October/2008

What is the usual price of fish tank lighting?

In my experience the most lights can be bought from $40 up to $400. It all depends on the fact if you’re buying a whole canopy bulbs, if there is a timer, and the number of bulbs. I am using AquaGlo Oceanic bulbs and they cost approximately $15/bulb. So if I bought canopies for 10 bulbs along with AquaGlo bulbs, then it could cost $225 in total ($45 for 1 canopy that houses 2 bulbs). As time goes by, I’ll have to change bulbs only. In my opinion this isn’t too expensive.

Can I use neon light for aquariums?

Yes, you can. Just I am not sure if plants are going to appreciate the given spectrum. But again, I have seen ordinary neon lights working well with aquariums.

Feel free to visit Aquarium Lighting at firsttankguide.net too!