[Recon Aqua Dog]

I setup new 80 gallon tank which has been running for 2.5 months now with refugium and all was well until I have two pieces of Fiji branch to finish my mangrove similation so to speak. I'm using zap gel -PT26 with fine results and someone brings home some Aqua stick epoxy to try for a better hold an as soon as we mend up one piece with epoxy my fish tank starts foaming like crazy???????? It's been 48 hours now and as soon as protein skimmer runs it causes mad foaming.BAD.... All tests are perfect still!!! Now
common sense says water change but I'm looking for answer why?