Putting Vitamin c in their water is not recommended. It changes the flavor if the water, then will cause your Guinea pig not to drink. Secondly if you have more than 1 Guinea pig, you cant control of amt of dosage they are drinking from the water. Recommended to syringe feed them 1ml of children's liquid. You should watch Scottys Animal You tube channel. Talks about importance of Vitamin C. https://youtu.be/7KTl08JDyas. How this helps.
Do not give in the water. There is a children liquid that is highly recommended that you give orally. There is also vitamin c tabs/wafet for Guinea pigs that they love. Please read about the proper care for Guinea pigs at guinealynx.com.
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