I am buying a used Deep Blue 80 gallon frag setup - it is 48" wide, 24" deep and 16" tall.
What would be a good LED system for a reef setup that won't cost me $1000? I assume I need two lights.
A quality setup that can grow anything, deliver pop to your corals, shimmer and once dialed in is virtually set it and forget it is the Photon 48. Comes with a 2 year transferable US warranty and one of the big pluses for me is the unit is user serviceable. If something should fail, rather than sending it away for repair leaving you with out a light for several weeks, you can easily swap out LEDS, drivers, the controller, etc. without voiding the warranty.
The ReefBreeders Photon 48 is fully programmable for an automatic sunrise/sunset/moon light simulation. This is a huge benefit opposed to just dimable lights on a timer because the 24 hour light cycle is automatic including the moonlights.
https://www.reefbreeders.com/shop/photon-48/
Now, you may find that ANY led setup alone will work, but not as well as adding a supplement like T5's. LEDS by the nature of their design don't blend spectrum all that well and tend to spot light which means you can have corals do great in one spot of the tank, but not so great in another. To cure this you can add 4 of these SunBlaster NanoTech T5 fixtures to your setup. Two on either side of LEDS. The fixtures won't break the bank as you can find them for ~$30 each. Each fixture can be connected to each other to run on one circuit on a timer or aquarium controller. They come in 2, 3, and 4 foot sizes, however, note that the 4 foot size is greater than 48 inches, 49 and change. So you may need to go to the 3 foot fixture to avoid light spillage or if your captured by a canopy. Don't forget you're also going to need to buy bulbs approximately every 6-9 months. ATI is the bulbs you want.
http://sunblasterlighting.com/nanotech-t5ho-reflector.php
This setup is proven to provide excellent growth for corals assuming you keep your water parameters stable and within acceptable ranges. JanesMW (Mike) has been running this setup for a while with good success and I will be running this exact setup on my 310 gallon upgrade.
There's plenty of other ways to light a tank, this is just one that works very well.
Hope this helps.