I bought an Eheim second hand and, during testing, I didn't notice any leaks. This weekend, I reconnected everything (so I could connect the shut-off valves) and then there was a small leak from the outlet nipple. I added some thread tape there and it helped a lot but the leak is still there. Just VERY slow. (I can only feel some water there after an hour or two.) What's the best way forward? Add more thread tape? Just tighten it more? (I have very soft, weak hands. So it's genuinely possible that I didn't tighten it nicely after I got tired.) I DON'T wanna break the thing. I'm scared if I over tighten it, I'll break the fastening ring. Am I just being TOO careful? Thanks folks!