Limto
Weren't compatible or it just exceeded the weight allowance? Because I did the same thing, but for weight. I used my saved treats at the start on the elder rod, and eventually got the best line and best reeler, but i could only apply one or the other to my rod.
The weight on the rod is not coordinated with weight of the fish or whatever. Its directly related to the weight of the accessories that you put on the rod. So with the elder rod, you can have the triple hook, the jade reeler, and you're pretty close at that point. Didn't test it out with lesser lines because I just bought the jade rod instead and was able to put both jade accessories on my rod. But with those two things I mentioned on the elder rod, you could do some deduction math and see what line you could add without going over - but honestly I used just those two accessories and the default line and did great. Plus there's a couple tricks I could show you in game that almost completely eliminates the need for tension upgrades.