You have 3 options when hanging your ati if you don't want a canopy:
1. The including hanging kit which I used. (Don't just mount to dry wall, use joists or mount a 1x4 between two joists and attach the fixture to that. You can paint the 1x4 to match your ceiling. That is what I did)
2. Create hangers out of bent pipe conduit from Lowes or home depot. Attach the hangers to the back of your stand with metal conduit mounting brackets.
3. Fabricate acrylic "stilts" that fit on the rim of the tank and hold the fixture (not pretty imo and difficult).
I recently upgraded from a 40b to a 90g and kept my 36" 6 bulb ati sunpower. It's hanging in the middle of the canopy from a bar that I can pull out to remove the fixture to clean or change bulbs. I then have 2 kessil a350ws mounted to each side of the canopy pointing down across the tank. I used these awesome low profile articulating mounts specifically designed for kessils. They screw right into the canopy and have an outstanding range of motion:
Articulating LED Mount for Kessil LEDs | Premium Aquatics
https://premiumaquatics.com/product...il-leds.html?gclid=CMDrzsH0zdQCFZZWDQodWJkJqg
BTW, although I personally would never hang the fixture from the ceiling/drywall/plaster without using joists or the 1x4 method, people have had success using butterfly bolts or other similar devices that spread the weight out across a larger portion of the ceiling material than if you were to simply screw the hanging kit into the ceiling. I believe the fixture comes with some but I would upgrade to larger ones for added stability if you go that route.
As far as mounting kessils to the ati fixture itself, you would not be able to use the splash shield (which is also an integral part of the cooling system as it directs the air flow from one side of the fixture out of the other). Your best bet would be to mount each one on the side rims of the tank with the articulating arms they sell, or, you could screw in some sort of bracket to clamp the articulating arms to on top of the fixture and bend the lights down towards the tank. Just make sure it's mounted securely due to the added weight.
If you aren't set on kessils, reef brite xhos (tech strips won't show up much when all t5 bulbs are on) can be mounted to the ati fixtures on front and back with easily findable prefabricated brackets.
Good luck!
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