I never unplug or switch off anything when I do water changes. Canister intakes are just below half way down the tanks so that I can do 50% changes. Internals are stuck to the glass and I just move them lower by sliding them. Believe it or not, HOB filters have never caught on in the UK. There’s hardly a shop here that sells them, or an aquarist that uses them. I can literally count on one hand the number I’ve seen in 51 years of fishkeeping.
Heater/stats are almost horizontal, in the lower half, so they don’t need to be switched off. I’ll never have one vertical because then the heat goes straight to the stat, which switches them on and off more than is necessary, shortening the life of the stat (imo).
Cichlid is pronounced sick-lid.
I’ve heard them all… Chick-lid, Chillid, Beta (a very common misspelling and mispronunciation), Chara-sin (it’s Kara-sin), Gwar-mee, Plate-ee, Goop-ee, Bircher (It’s spelt Bicher, and it’s pronounced Bish-er). And many others I can’t think of right now…