21" deep freshwater lighting

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Jan 6, 2019
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Hello everyone! A couple years back I bought a 36 gallon 21" deep aquarium and it’s sat empty for a long time. I’m just now looking into getting lights for it and I know that finding good lights for such a deep tank is difficult. My goal is to grow medium-high light plants (though I’d be fine with medium light plants seeing as high light plants in deep tanks are especially hard to grow).

My question is: what lights would work well to grow plants in that deep of an aquarium? I’ve heard about T5HO fixtures/bulbs, but there’s so many options that it’s a bit confusing. Would I be able to get away with one light or would I need several? If not the T5HO’s, what would work? I’m open to all ideas and appreciate anything people can tell me. Thank you!
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21 inches high isn't deep. A normal LED light unit should be sufficient if the unit has different light intensity settings.

HO T5 lights are obsolete due to LED lights being just as bright and cheaper to run. LEDs don't need to be replaced either so you save money by not having to replace globes.

You can set up most LED light units to come on with a low intensity light and increase during the day, before reducing at night. You can also increase or decrease the various wavelengths of light in a lot of LED light units.
Oh ok, good to know. Thanks! Are there any particularly good brands or anything I should look for? My aquarium is about 30-31 inches wide if that helps. The only LEDs I’m used to are for reptiles and aren’t adjustable so I don’t have much experience there. Thanks so much for letting me know though, I appreciate it!
I’ve used sky Nicrew led’s for that size tank with no problems.Their reasonably cheap.You can adjust light intensity and I use mine with a timer so they ramp up and off.
My largest tank is 67cm deep (26.3" -ish) and my Fluval Aquasky lights work just fine for plants. Bluetooth, fully programmable etc. On the pricey side though and if the programming isn't important to you then there are much cheaper lights out there.

As Colin said, it isn't deep and standard LEDs will work fine. I've used Nicrew lights on other tanks too, as recommended by Moby, and never had an issue.
Awesome, thank you so much everyone! I’ll look into both lights and see what works for me :)

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