Am I looking for a lower or higher percentage of phosphorus and magnesium?

I guess I need to find out what makes a good urinary wet cat food and start looking for that nutrient percentage. My cat had a bladder infection one time at 5 years old and the vet put him on the prescription diet. Not sure if he really needs it or not, my cat shows signs of being scared and has high anxiety and I think he just didn't like going through the cat door or the sound of the fan in the closest so he held his urine causing the bladder infection? I already changed the dry food to a cheaper brand over 2 months ago and he's doing fine. Just need to go from $3 a can to more like $1.50 for a 5oz can.

I don't even pay $10 a lb for the food I eat.

You are looking for a lower amount of magnesium and phosphorus. The chart I attached earlier is dry matter not as fed.

Here is the chart for as-fed.

I got a lot of info here https://catinfo.org/feline-urinary-tract-diseases/

When I had a cat, he had the urinary tract problem. He got plugged up after me having him only a couple months. They told me it was too much magnesium in the food and recommended Science Diet. No way I could afford that. I took the label to the store, and found that Purina One Urinary Tract food had the same low magnesium. I fed that to him for 12 years, and he was still perfectly healthy when he got loose one day and never came back.