Gotta say, right off the get go.......the '5 degrees a week' thing is not necessary for chicks.....and could be harmful, hot chicks can be sick chicks.
Here's my notes on chick heat, hope something in there might help:
They need to be pretty warm(~85-90F on the brooder floor right under the lamp and 10-20 degrees cooler at the other end of brooder) for the first day or two, especially if they have been shipped, until they get to eating, drinking and moving around well. But after that it's best to keep them as cool as possible for optimal feather growth and quicker integration to outside temps. A lot of chick illnesses are attributed to too warm of a brooder. I do think it's a good idea to use a thermometer on the floor of the brooder to check the temps, especially when new at brooding, later i still use it but more out of curiosity than need.
The best indicator of heat levels is to watch their behavior:
If they are huddled/piled up right under the lamp and cheeping very loudly, they are too cold.
If they are spread out on the absolute edges of the brooder as far from the lamp as possible, panting and/or cheeping very loudly, they are too hot.
If they sleep around the edge of the lamp calmly just next to each other and spend time running all around the brooder they are juuuust right!
The lamp is best at one end of the brooder with food/water at the other cooler end of the brooder, so they can get away from the heat or be under it as needed. Wattage of 'heat' bulb depends on size of brooder and ambient temperature of room brooder is in. Regular incandescent bulbs can be used, you might not need a 'heat bulb'. You can get red colored incandescent bulbs at a reptile supply source. A dimmer extension cord is an excellent way to adjust the output of the bulb to change the heat without changing the height of the lamp.
Or you could go with a heat plate, commercially made or DIY: https://www.backyardchickens.com/a/pseudo-brooder-heater-plate
There's a
lot of info out there, some of it not quite right....and there's always multiple opinions...and multiple things can work in the right situation and not in others.
My advice is read it all, apply copious amounts of common sense, and don't jump to any absolute conclusions.
Yes, raising chickens can be easy peasy, once you've got some experience under your belt it's a piece of the best cake ever.
....BUT.....
There
is a steep learning curve with all the little details that can make things difficult or easier, it's like trying to get a drink out of a fire hose sorting it all out.
It'll bend your brain.
I spent
months wading thru all the advice and ideas on this forum, learning to distinguish the fallacy from the facts, identifying the people that had a good head on their shoulders and experience to boot, taking lots of notes, and planning and re-planning my coop and run. When I finally started building them I was d@mn glad I had taken the time to research first as I made most my mistakes on paper, so to speak, rather than in materials and rebuilds. Made it much more pleasant when I finally got my birds into a well planned facility to then observe and learn about all their odd behaviors..... which to worry about, which needed management and which to just laugh at.
Welcome to the Chicken World....Good cLuck and Have Fun!