firstly how far do you cast? if its only 80 to 100 yards then 120 meters of braid will do ya ,you will need backing of mono to ensure you fill the spool to aid casting ,if you have a spare spool put on your shockleader then braid and then your backing till the spool is full to within a mil or so of the lip ,swap spools and wind the whole lot back on the other spool ,if not just guess
,20 or 30 lb braid is ok for bait fishing ,30 prob better if you fish mixed ground,as for what brand it depends on your budget and where you intend to buy it ,i have used diawa,spiderwire,berkley big game, penn, fladen warbird and power pro and to be honest for bait fishing they will all do the job.i like spiderwire code red as its easy to see at night compared to the green ones power pro comes in red and high vis yellow too .
excpect to pay about 20 euro for 120 meters ebay can have some good deals but keep an eye on the postage as its often the same price in your local shop by the time you add it on
it will last for a long time for cleaner ground fishing,i have code red braid on one reel two years and am still fishing with it