Sometimes you get what you pay for with lighting. What's the max budget for the 20g lighting? What do you want to grow? Low light plants, medium, high?
But for budget lighting, I think Aquatraders is known to have inexpensive options for T5 and LEDs.
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Just know with moderate to high lighting you'll need to get a good fertilizer regimen going and carbon source such as Glut/Excel or CO2. But in return you'll get faster more lush growth and can even grow carpeting plants like DHG (and other more demanding species).
But if you're happy with low light tolerant (low-tech) plants, then go with Brookster's feedback since he has experience with that particular Tetra lighting.
If you're able to wait & save some money (and boost your budget), I encourage you to invest in a solid well-regarded lighting system. Do some research and check reviews. You can always go "budget" on other aspects (i.e. ferts, co2, substrate, etc), but I personally wouldn't skimp on lighting. I'd go with either the Finnex Planted+ or Current-USA Satellite LED+. These are great options for the value and will last you years and will grow a good amount of plants you throw at them.