I would honestly say dont worry about it too much, if its turning even pale pink then there are ketones present. It may be pale because you are drinking lots of water which may dilute them in your urine, but that doesnt mean they are not there in your body doing what they are supposed to do.
I think you have to remember that ketones alone are not responsible for you losing weight on Exante, especially if you are doing 3 packs a day with no other food, its so low in calories, that the low calorie intake is going to make you lose weight on its own, its just that being low carb you also get the benefit of being in ketosis too.
Testing for ketones is probably more useful if you are doing a meal a day as well as the exante, to ensure that you are eating the right low carb food in addition to the meal replacements.
Testing for ketones if you are on total solution with exante (ie 3 packs a day and no other food) is a bit of a waste of time, but reassuring to see the strips turn pink. If they turn dark pink or purple, then it probably means you are not drinking enough water, you do need to keep flushing them out of your system so lots of water is important ( but not 3 litres in 2 hours which can be dangerous)
