I have a 55 gallon tank. 48”x21”
So a standard 55 gal. 12" wide 21 deep.
I'm not going to debate the "suitable for" part but the light is like 19 watts which will be low par at the substrate level.
As an example.. 2 48" Beamswork DA-Fspecs can probably put you at about 100 par at the substrate level.
colr temp of these lights ias around 12000k-ish.
48" is listed at like 60W but that is system watts.
So they can be "suitable for marine" in a sense.
These are one of my least fav fw look lights. Too cool.
But they are relatively cheap, been around a long time and decent power/$
The below par chart is for one 24" light btw:
Find aquascaping PAR data of popular fixtures. This currently and in the future will include products such as Finnex, Beamworks, ONF, etc. Submit a request if you would like a fixture tested!
aquariumpardata.com
Cost is $70 each and a timer/dimmer is optional @ about $15.
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Amazon
DA FSPEC LED Aquarium Light Pent Freshwater(120cm - 48")
Biggest issue w/ your tank is the 4/1 L/W ratio. Hard to "do" pucks especially symmetrical.
Even the "black boxes" are problematic because you really need 2.. bringing the cost up to $300 currently.