Reactor chamber leaky fix?

[minus9]

I just picked up a second chamber for my CaRx and discovered it has a small leak in the intake. I can't remove the fitting (looks like it was repaired before), but wanted to know what I can do to seal the leak? If anything? Weld on #40?

 

[Lovemyreef2015]

Maybe using Aquarium silicone? Here's a bump to see what others think

 

[minus9]

Maybe using Aquarium silicone? Here's a bump to see what others think

Thanks! I may try to clean up the glue that's on there now and see if I can free the fitting, then maybe use some weld on 16 to seal it?