i have an elm rod "skill rank req: 10 (tier iii)" that i am able to equip and use

and then i have another rod with "skill rank req: 45 (tier x)" that i cannot equip

my fishing proficiency is 4......


what does the skill rank mean? are equip-able fishing rods based on your proficiency and fishing rod tier level?

example
a level 4 proficiency in fishing i can use a IV level fishing rod and no higher?

eh?

your proficiency determines what level rod you can use and what kind of fish you can catch. I'm not sure about the max level rod you can use though (4 prof using 10 skill rod vs. 4 prod using 45 skill rod), hopefully someone else is knowledgeable.

The list below will show you what kind of fish you can catch at every level: http://ladderslasher.d2jsp.org/index.php?g=14#Fish

For every 5 levels of profiency you can use 1 tier higher rods, so prof 1 tier I rods, prof 5 tier II rods, prof 10 tier III rods etc.
Though you can use couple tier higher rods too if you want, using those makes fishing just a bit slower.

thanks for the info