Hi Cindy! 3 units is a large dose for so early in treatment! Most cats should be started at .5 to 1 unit twice a day and increases done in .25 to .5 unit increments so I'm concerned your cat is getting too much insulin but we're here to help you!
First, the food you're feeding is very high in carbs! 36% on a dry matter basis is over 3 times as high as we recommend. We suggest feeding a canned or raw diet that's less than 10% carbs. We have many cats here with IBD along with others with a history of crystals so you're not alone.
The cats with a history of crystals were switched to a low carb canned diet with extra water mixed in and did great. Cats were designed to get their moisture from prey so feeding canned food with extra water mixed in helps to keep the urinary tract flushed out. The solution to pollution is dilution!! Lots of great information on
Dr. Lisa's website on Feline Nutrition.
I'm surprised that Tansi can tolerate the RC Gastro if he has IBD. From the ingredients list, there are several very common trigger ingredients that most cats with IBD can't eat at all.
Water Sufficient For Processing, Chicken Liver, Pork By-Products, Chicken By-Products, Pork Liver, Chicken, Corn Flour, Powdered Cellulose, Pork Plasma, Modified Corn Starch, Natural Flavors, Gelatin, Calcium Sulfate, Fish Oil, Sodium Tripolyphosphate, Potassium Chloride, Carob Bean Gum, Sodium Silico Aluminate, Vegetable Oil (vitamins and minerals)
Chicken is a common problem for a lot of IBD cats, along with corn and a lot of fish oils. (the RC also contains my personal pet peeve ingredient laughingly called "powdered cellulose"...that's basically a fancy word for sawdust)
But before you change the food, it will help if you'll start using the spreadsheet we all use and put in some of the data your Libre has saved for you (at least the last 2 weeks if you can). Here are some tips on
How you can help us help you that include links to how to set up our spreadsheet, get your "signature" done. We're very data driven here so getting those 2 things done will really help us to give you the best advice possible.
transitionint to a pet glucose monitor.
You might want to see if you can cancel/return that. The pet meters are fine meters, but the strips for them are about $1 EACH. We recommend testing at least 4 times a day (more if your cat is dropping fast or low) so it can cost a lot to use!
Most of us use human meters you can get at any local pharmacy. Since you're in Canada, the Contour, Freestyle and One Touch (most places give you the meter free if you buy 100 strips).
Another meter that's gaining popularity in Canada is the Bravo meter available here:
http://www.diabetesexpress.ca/free-meters-more-free-bravo-meter-with-purchase-bravo-test-strips-p-2456.html It's definitely the most affordable!!
Don't want to overwhelm you with too much, too fast! Do you have any questions we can answer for you?
ETA...I saw your other post that you don't have a computer and aren't sure about using your smartphone. We can set up the spreadsheet for you and help you learn how to use it but you need to make sure you can download the Google Sheets and Google Drive apps onto your phone.