That would be incorrect. You should say "I don't have so much water" instead, or "I don't have that much water," with the latter one being the one that you would most likely hear in a typical conversation.
Thanks.. but i was following the example of the previous post. The point of my post is to show show the 'have got' construction being an acceptable alternative for 'do have' (just in case you missed, which i don't think you did).
That much, this much, so much should be all the same. The meaning is conveyed by stressing the word before ''much''. If Duo doesn't accept ''this much'', please don't put ''this'' in the choice of words.