How big a tank will one Hydra 32 HD light?

AquaIllumination rates it for about a 24 by 24 inch area, roughly a 45 gallon reef. Wider or deeper tanks usually need two units for even coverage.

Does it work without the Mobius app?

It runs on its own schedule once set, but setup and changes go through the Mobius app over Bluetooth or Wi-Fi. There is no separate wired controller.

Yes. Its 90 W output and blue-heavy spectrum suit SPS and mixed reefs, provided the light is placed high enough and coverage is adequate.

The 32 HD adds output and a thinner body over the 26 HD, with the same app control. It is the stronger choice for deeper or more demanding reefs.

You get the fixture, a power supply and a mounting bracket. Tank mounts and rail systems are sold separately.

Yes, with a hanging kit or rail. Keep clearance for the fan and avoid enclosing it where heat builds up.

At BulkReefSupply.com, for $407.90, as of our latest check.

12 stores we checked sell it, including BulkReefSupply.com, Top Shelf Aquatics, Fish Tanks Direct, TRSC Aquatics, The Fish Room.

$407.90at BulkReefSupply.comChecked 8 h ago

Compared across 12 stores. Prices are checked against each store and labelled with when.

It checks today's price at every store, compares the alternatives and answers in about a minute.