Most of you viewing this wouldn't probably want to know the lower level steps to fishing like from level 1 do shrimps, so I am going to skip all that and just mention the best and common ways to get 99 from any specific level.
Lobsters- Level 40+
These are a good moderate way of gaining fishing experience as well as money. Although the price has dropped recently, they are still a useful source and is probably one of the best ways for non members. Runnning to Stiles and returning to fish will get you quite a lot of money. I recommend you bring an explorers ring 3 to improve speed now and again if you're in a hurry.
Tuna/Swordfish- Level 30/50+
While tuna may be a good way to level up until you can do lobsters, swordfish have proven a useful way of gaining experience, especially with the help of the swordfish gloves obtainable from the fist of guthix activity. These serve as decent money, however because you also catch tuna with them, it isn't a very reliable source unless you use the gloves. Nonetheless this is a good way for non members if you drop all the tuna, just keeping the swordfish instead. This can also grant more experience in the long run as you'll be making less trips to Stiles, but perhaps less money at lower levels because of the chance that you my catch tuna.
Monkfish- Level 62+ (Requires: Swan Song Quest)
Monkfish are a very good high level fish, which grants moderate amounts of experience as well as money. While some may get bored of fishing them, it can still be a useful way of gaining levels as the raw fish are often used by cookers who wish to level. This should be the next level up if you're still fishing lobsters. They are close to a bank, moderately fast and you can talk to the fishers or do something else while fishing.
Leaping Fish- Level 30+
While it is not recommended to fish these at level 30, but at higher levels so you are able to catch the leaping sturgeouns, these offer the best rate of experience in fishing in the entire game. However no money is gained from this. It is considered to be even better than fly fishing, and as an added bonus it also grants strength and agility experience. The only downfall is the repetitive dropping of fish and lack of bank nearby. You could still make some money by cutting the fish and keeping the more expensive parts, however I recommend you use the fish cuttings for bait instead.
Trout/Salmon- Level 20/30+
These are one of the most common ways of levelling the fishing skill. If you bank (best place is Shilo Village, and a lesser known area is North of Camelot) you can gain some money, however these are mainly fished for experience and then dropped which is known as powerfishing. If you are unconcerned about money, this is a good way to level fishing unless you want to do barbarian fishing which is a better alternative.
Sharks- Level 76+
These are a very good source of money, and while the competition has fallen with the newer fishes being released, these can still be served as a purpose with higher fishing levels. Although the slow catch rate means less experience overall, with shark gloves these can be a decent way to increase your level. They are also a good alternative for those who go AFK often. At higher levels, it's worth hand fishing them for the extra experience in other skills as well as the chance that you'll get multiple sharks.
Cavefish- Level 85+
Some guides recommend these, and while they are a useful way of gaining experience, you are better of leaving them until you access the more superior rocktail which offers the best exchange of experience and money. Cavefish are still good and not to be taken lightly, if you can handle the slow catch rate and the constant lag if you use world 84 to avoid the rock protectors/followers. These are quite a quite useful if you're ever feeling bored because you can be on another tab on the internet while fishing these.
Rocktail- Level 90+
These fish are considered the elite due to their high requirement. However they serve as the best fish for both experience and money. While other methods grant higher experience such as barbarian fishing, these give a large amount of money as well as a high amount of experience per hour than any other technique. It is worth your time to fish these even at Level 99, and the slow catch rate and safety if you are in the unofficial Living Rock Cavern worlds ensures you can AFK train with ease.
A good way to see if what you're fishing is worth the time, check the Runescape Grand Exchange
This concludes the list and while there are other options of fishing as well as activities, and other items such as the sacred clay harpoon, they are up to the person and I have not included them as these choices are the best in terms of experience rate. I hope this helps you and you to take up the road to 99 fishing. The cape certainly is worth it.
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