Max 180w LED output for 2x4x6 tent with 3 plants. Good enough?

This light looks like the old Viparspectra or Mars Hydro of a similar class. To get the most out of space available you may need another light to increase your light footprint (if maximum yield amount is your goal). The LED looks like it could handle a 2x2 footprint during flower. You could set it up in the middle but the growth rate will taper off as out get outside that 2ft box. You can make it work but if you have the resources I would try to get a second light. Good luck.

That will probably work well for veg but purple lights usually dont build good flowers. I would look at getting a 240w quantum board kit.

You will need to look at the information specification of the light's umol/s output and distance w x l x h. Then work out the corners of the light if you getting sufficient DLI for the side plants. example to work out DLI is below 1000umol/s x 3600s x 18hrs ON divided 1,000,000 =64.8 once you switch to flower 1000x3600x12/1000000 = 43.2. It drops significantly so you can decide if you need extra light. Cannabis will grow well 28 to 45, of course the higher the better! And other factors also changes things. now you know the calcs u can decide yourself 😂