My Red Dwarf Gourami and Pleco are glass surfing like crazy lately. Two angels seem to be staying together but away from the activity. Think it’s freaking them out a bit. Thoughts?
Any chance you could get some video of the tank and fish? Others will be able to tell a lot from the behaviour. Video upload feature here doesn't work, but if you upload to youtube then link it here, people can see it then.
Sometimes glass surfing a bit can be normal. Like when a fish is newly introduced to a tank and not settled in yet, if the glass they're surfing is especially reflective, sometimes my cories and otos will do a little glass surfing when they're getting worked up and about to get frisky - but then it's short in duration.
If fish in a tank they're established in suddenly start glass surfing and it's unusual for them/they're not spawning, could be a problem with water parameters, so worth checking those. But especially with angels, and you say that the two angels have been pairing up recently... makes me think much more likely that they've formed a pair, and a pair of cichlids don't like others in their territory when they're wanting to breed. Have seen pics and videos of two angels calmly swimming around a tank, while every other tank mate is pressed up against the glass on one side, trying to avoid the angels, that have decided the whole tank is their territory, and they're not going to tolerate others being in there.
Will mean removing fish and changing things up, because the next step is the angels killing the other fish, if they don't get out of their territory, and the other fish cannot escape the glass box they're in, so require our intervention.