One of the decisions you must make when purchasing an aquarium is choosing the type of light you want. However, the decision doesn't end there. Choosing the proper size fixture and replacement tubes/bulbs can also be a challenge, especially months later when you may have to replace a bulb and have forgotten what size you originally purchased.
These charts shows standard fixture and tube sizes for various size aquariums, as well as information about specific brands of light fixtures. Print off a copy before you go to the store -- it will come in handy when purchasing a new light fixture or looking for replacement tubes. Keep in mind that your old tube probably has a code on it indicating what type it is. You can find some basic info explaining those codes in my bulb letters FAQ.
Standard Fixture and Tube/Bulb Sizes
This table is a general rule of thumb. If you know the specific product you have, or will be purchasing, check the manufacturer tables below for details. I'll add more manufacturers as I obtain product specifications.
| Fixture | Fits Tank (gallons) | Bulb Size |
|---|---|---|
| 20" | 10 | 18" |
| 24" | 15, 20H | 18" or 24" |
| 30" | 20L, 29 | 24" |
| 36" | 30, 40H, 50, 65 | 36" |
| 48" | 55, 60, 70, 90 | 48" |
Tube Diameters
Tubes of the same length may not be the same diamter. Most aquarium light fixtures acccept T8, T10, and T12 tubes, but it is wise to verify which sizes your light fixture accepts before purchasing a bulb. You can usually determine the diameter of a tube by checking the codes printed on it. If you are unsure of what the codes mean, check my bulb FAQ for further details.
Compact Lighting
Intended for small aquariums that require more light, such as tanks with live plants or saltwater corals. The fixtures generally range from 12 to 24 inches, however some manufacturers make them in longer sizes. Due to the specialty nature of this product, I am not providing tables at this time for this type of lighting.
Eclipse Hoods
Eclipse units include a filter and light, so this chart provides filter data in gallons per hour. Note that the Eclipse Model 1 comes in two versions, the second having an extra bulb.
| Model | Size | Filter | Bulbs | Fits Tanks |
|---|---|---|---|---|
| Eclipse 1 | 10" x 20" | 150 GPH | 1 - 18" bulb | 10, 15, 18H gal |
| Eclipse 1 | 10" x 20" | 150 GPH | 2 - 18" bulbs | 10, 15, 18H gal |
| Eclipse 2 | 12" x 24" | 200 GPH | 2 - 18" bulbs | 15, 20H, 25, 30T gal |
| Eclipse 3 | 12" x 30" | 200 GPH | 2 - 24" bulbs | 29, 30, 37, 40T gal |
All-Glass Fluorescent Strip Lights
| Fixture | Fits Tank (gallons) | Bulb Size |
|---|---|---|
| 20" | 10 | 18" bulb |
| 24" | 15, 20H | 18" bulb |
| 30" | 20L, 29 | 24" bulb |
| 36" | 30, 40H, 50, 65 | 36" bulb |
| 48" | 55, 60, 70, 90 | 48" bulb |
All-Glass Twin-Tube Strip Lights
| Fixture | Fits Tank (gallons) | Bulb Size |
|---|---|---|
| 24" | 15, 20H | 2 - 24" bulbs |
| 30" | 20L, 29 | 2 - 24" bulbs |
| 36" | 30, 40H, 50, 65 | 2 - 36" bulbs |
| 48" | 55, 60, 70, 90 | 2 - 48" bulbs |
All-Glass Deluxe Full Hoods
These units include a complete cover for tank top with knock out areas for installation of heaters, power filters and other accessories.
| Fixture Dimensions | Watts | Bulb Size | Fits Tank |
|---|---|---|---|
| 20" hood 9-3/4"W by 3"H | 15W | 18" bulb | 10 gal |
| 24" hood 11-1/2"W by 3"H | 15W | 18" bulb | 15, 20H gal |
| 30" hood 11-1/2"W by 3"H | 20W | 24" bulb | 20L, 29 gal |
| 36" hood 11-1/2"W by 3"H | 20W | 24" bulb | 30, 40H gal |
| 48" hood 11-1/2"W by 3"H | 40W | 48" bulb | 55 gal |
Perfecto Fluorescent Strip Lights
| Fixture | Fits Tank (gallons) | Bulb Size |
|---|---|---|
| 20" | 10 | 18" bulb |
| 24" | 15, 20H | 18" bulb |
| 30" | 20L, 29 | 24" bulb |
| 36" | 30, 40H, 50, 65 | 36" bulb |
| 48" | 55, 60, 70, 90 | 48" bulb |
Perfecto Fluorescent Two Bulb Strip Lights
| Fixture | Fits Tank (gallons) | Bulb Size |
|---|---|---|
| 24" | 15, 20H | 2 - 24" bulbs |
| 30" | 20L, 29 | 2 - 24" bulbs |
| 36" | 30, 40H, 50, 65 | 2 - 36" bulbs |
| 48" | 55, 60, 70, 90 | 2 - 48" bulbs |
