I like to raise or lower over 24 hours using the
heater drop it or bump it by a degree every couple hours, and in a pinch would take out and add water that is warmer to bring it up slowly. I don't recommend a fast increase or drop that might stress the fish and lower its immune system. 74 isn't a big deal, I normally run mine from 76-82F depending on whether I'm resting or breeding them or raising fry, running it hotter for spawning, or fry raising, running it
cooler for resting the parents. Under 70f would be a cause for concern, especially under 65f.
Keep an eye out for a sign of
ich in the next couple days sometimes the rubbing can indicate the external parasite is present but not yet visible on the fish.
Also that could have just been "
flashing" and you've never seen it before from the fish. All
cichlids do it, angels don't do it very often but it happens from time to time where they will jerk on the substrate or "tabletop" briefly. My angels sometimes act crazy if they were sleeping and just woke up also especially if they dozed off and drifted into a tight spot. I don't think the 74f and cold fish was the issue. Could be a female exhibiting spawning behavior possibly also, they will rub close to objects and leaves and peck at the and suff to clean an area to lay eggs. Even a solo female will do it unpaired when they reach maturity and lay eggs that can't be fertilized sometimes.
