Yes, do not share leeches! And some problems can arise from feeding leeches your own blood. For example: my leech bite wound didn’t stop bleeding for 2 days after a feeding. Though, this could have occurred because the leeches fed so close together. Anyway,
Leech feeding alternative: blood sausage.
(Some leeches might eat chicken livers or other things like that, but I haven’t had luck with feeding medical leeches that way.)
How to make “blood sausage.”
-Buy some blood from your butcher. (Mine was only $15 a gallon, and was special ordered. Make sure to order unseasoned!)
-Buy some sausage casing. (Cheap.)
1. Make sure to rinse out the sausage casing, as it is covered in salt.
2. Tie on end of sausage casing, and then fill with the blood like a water balloon. Tie off other end.
3. Warm it in the microwave for just a few seconds. I always kept my blood frozen, and then thawed every time they needed to be fed. So just make sure it’s a little warm before you plop it in the feeding container or the leeches won’t be interested.
Also, I recommend you feed your leeches in a separate clean bucket or something than you keep them in. It’s kind of messy and blood is really gross when it’s not cleaned to pristine conditions afterwards. :)