Ketosis - different readings even tho 100%?

Hi, can anyone help me out with this pls;

I've been 100% for x2 weeks and a couple of times I used the ketosis sticks and had a very strong reading but today its showing a very weak ketosis reading (hardly any trace). If I'm 100% and doing the same thing each day ie water and x3 shakes why would the ketosis reading differ?

It will change with the water you drink during the day, like not drinking much and your pee being strong yellow. It's the same with the ketones in your pee you have just weakens the concentration that's all. The stick are rubbish also if you stay at dark purple it means you are dehydrated and need to drink more, strong ketones are not healthy.
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