I had a bunch of Guppy fry make it through Quick Cure, Triple Sulfa, Fungus Cure, and 88F temps without an issue (not all at the same time), they are pretty tough. If you do not plan of feeding the fish for 5 days though, not many will make it. Fry do not have much for reserves like a grown fish and will quickly weaken if not fed. Also, your other fish will be more likely to eat the fry if you do not feed them for 5 days.
You CAN do water changes and still treat the medicine correctly by replacing the ammount you took out. You just need to add back in extra medicine in the same percentage of water you changed. For examaple...
Day One: Do a water change, then put in one tab.
Day Two: Do a 25% water change, put in 1/4 of a tab, then put in another whole tab
Day Three: 25% water change, 1/4 tab + one full tab...
This has worked perfectly fine for me and a few other people on here. I strongly feel this would be much better than dosing an uncycled tank and stressing the fish even further.
And just remove the carbon or you are likely wasting your effort. Carbon can be absorbitive for anything from a couple days to a few weeks. There is no easy way to know how much more your carbon can absorb. With most filters cartridges, you can just make a cut in them and shake out the carbon...
2x Sunburst Platys (2M, 2F) // 3x Neon Tetras (?) // 2x Cherry Barbs (1M, 1F) // 2x YoYo Loaches (?) // 1x Bushy Nose Pleco (M) // 1x Clown Pleco (?) //
-30# Live Rock
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-1x Royal Gramma // 1x Percula Clownfish
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