Newbie time

I have the ts1000, I have 27°C in my growbox and 26 in my water (too hot) But i think there is less heat than with the HPS.

CMH is far and away the best grow light out right now and here's why. I like many others ran old school HID for many years and after a few years I started hearing LED this LED that, LED, LED, LED, so I finally switched and went with a 3000K Quantum Board and after testing it over several grows I hated it, my plants were never healthy, they got deficiencies all the time and even though the yield was impressive I just got tired of looking at unhealthy plants. With CMH there is no try hard, your plants are beautiful all the time, they are healthy, vibrant because you get the true full spectrum of the sun, and deficiencies are a thing of the past because the plant metabolizes nutrients better, the only way you are going to get a deficiency is if you are just totally fucking up hard, and at that point you better start reading or get some help from an experienced grower. CMH is as close as you can get to the full spectrum of the sun and it's natural light with the only exception being LEP which is insanely expensive with extreme energy consumption and isn't a stand alone light. LED isn't ready, it's close but it just not ready, and until it is CMH is the best option there is.

mars are a lower efficacy, so more heat and higher electric bills relatively speaking to something with higher efficacy.. it'll be more than a few percent too.. Check out something similar to SF-1000. It uses Samsung LM301b diodes. They say 2.7efficacy, so it isn't pushing them hard. That mars likely isn't better than 2.1 at best.. Better HPS are around that range too, if not mistaken. 25% more efficient. Plus, those diodes last 60k hours before they dim to 80% intensity. I'm not advertising for that specific light. It is merely an example with the LED diode you want, and you are good. If they mix in some rar red, that's good too -- that's why the SF one isn't a slightly higher efficacy if it were all LM301B. Anyway, that light i have a concern about. You'd want a fan blowing across that heatsink -- the entire top + driver. I'd be worried about the heat on the unit itself, not anywhere near your plants. A dimmer switch is great for vege... save even more money. if using from seed to harvest, get something with a dimmer too. even if only ~50% dim, that's more than enough for what you'd need to adjust.. likely half that or less depending on height and footprint you need.