Your friend will likely suggest you do one of 2 things: 1) Take media out of his filter (don't rinse it but keep it wet with his tank water) and put it behind the new media in the new filter. I've done this and added fish (slowly) with no problem. Add some substrate from his tank and just put it into a nylon stocking in your tank. Borrow ornaments from his tank. Anything with beneficial bacteria on it (porous is better). I like adding live plants (they take up ammnonia etc...). - or - 2) Take your filter and run it in his tank for a couple of weeks, for extra insurance add some established media from his filter to yours and you're good to go. You can also do the gravel in the stocking - ornaments and plants.
Don't add delicate fish until your tank is fully established. I don't mean cycled but running for a long time. Feed lightly for the first couple of weeks.
Don't add delicate fish until your tank is fully established. I don't mean cycled but running for a long time. Feed lightly for the first couple of weeks.
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