You have to turn it off and on again and wait a few seconds. This is the known Problem as well as with hydrogenengines. Keen solved the Problem with the HydrogenEngines with turning em off after constructing. What do you mean with container?
Other Question, the Reactor is using Gas, so if the reactor can emtying his stored Gas can't ignore deuterium, cause he has a fueled inventory, or am I missunderstand sth.?

"You have to turn it off and on again and wait a few seconds." Alright, at this point i didn't waited few second. I only tried to turn the reactor on and off right away.
"This is the known Problem as well as with hydrogenengines. Keen solved the Problem with the HydrogenEngines with turning em off after constructing." I never heared of this kind of issue. So... i don't what are you talking about, sorry.
"What do you mean with container?" In the description it needs "deuterium". So i linked the reactor with any kind of deuterium ITEM (things you can pick up on the ground, so no fluids or anything else). It may sounds stupid 'cause i don't know how everything works yet. Beacause you're telling me this just at the end "the Reactor is using Gas", so i think the reactor do not use any kind of item.

In the end and if i undertand it correctly, the reactor is not like the vanilla hydrogen generator. You can't put items in the fusion reactor, beacause it's not using an inventory system. So it's using deuterium stored in a tank. It's still strange (maybe beacause i didn't waited long enough after turning it off), beacause i have a whole system (thanks to creative) with each kind of deuterium machine.
So if it's not working after waiting "a few seconds". I don't know what to do after this.

Thanks for the reply have a great day.

引用自 Kuvat：

You have to turn it off and on again and wait a few seconds. This is the known Problem as well as with hydrogenengines. Keen solved the Problem with the HydrogenEngines with turning em off after constructing. What do you mean with container?
Other Question, the Reactor is using Gas, so if the reactor can emtying his stored Gas can't ignore deuterium, cause he has a fueled inventory, or am I missunderstand sth.?

Hello again, i checked everything a moment ago. And it's working. I guess turning off, waiting a bit, and turing it on again, is the way to solve the problem.