Verging w/ 2 spider farmer se3000 want to flower with 2 600watt blackdog. Is there a better way to introduce the 2 blackdog without dimmers?

If you want to use them all in the same tent you might need to raise the lights up a good amount to control the amount of energy flowing into the canopy. Your will want to find your PPFD map for the lights in question. you should not be going over 1500PPFD without extra environmental controls like added CO2. one 600w light could do a 2x4 or 4x4 tent easy. Your two spider farmers are 300w each, total of 600w and you want to add in two more 600w lamps, totalling 1800w, TBH that's overkill if that's true power pulling from the wall. https://www.amazon.ca/Spider-Farmer-Spectrum-Commercial-Dimmable/dp/B08S73QP42?th=1 PPFD map listed on amazon page. https://www.amazon.com/Black-Dog-LED-PhytoMAX-2-Spectrum/dp/B072F2W1HJ no PPFD maping provided, if this is your model. I think that your spider farmer is a better light and you should just stick with them. Maybe use the black dogs for cloning or other projects. More light does not always equal better results there are caps. Best of Luck and Hope This Helps.