Take your scale with you to buy rodent and weigh rodents and buy ones that are 10%-15% of body weight. So if your snakes current weight is 155g then feed a rodent 15.5g-23.25g every 5 days. Make sure to weigh the rodent without the bag it's packed in. IMO I would switch to rats asap that way it won't be hooked on mice forever and then you will have to be feeding 3-4 mice per feeding every feeding. They make rats in all sizes so you can offer 1 appropriate sized rodent no matter how big your snake is. At 155g your snake can take rat fuzzies but if you can't get rats around the 10%-15% you will have to feed mice or order online.
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