At level 40 of fishing, you may fish lobsters at the island called Karumja, this time round, fishers do not need to bother about running out of feathers as the usage of lobster pots are unlimited unless you break them carelessly in the whirlpool. A normal raw lobster fetches a price of about 300gp at the Grand Exchange but however with recent statistics, the value has been rising about 5gp every week to about whopping 340gp!
At fishing level 50, you will be able to fish out swordfish; this fish is caught with a harpoon at Karumja and is worth about 470gp at the Grand Exchange. Its value, like the lobster, has been on the rise ever since but recently, its value has started to dip.
Some fishers may want to fish swordfish in preference to lobsters. However, harpooning catches tuna also and it is very irritating when you have to discard the useless tuna as they are worthless at the grand exchange. Through my studies, the only advantage of fishing swordfishes and tuna together is that their combined experience points are always higher than fishing lobsters. However, I have also studied that lobsters have far more advantage than swordfish and tuna:
Lobster pot constantly enables you to catch lobsters and thus takes up only one banking space inside your bank account. Harpooning catches tuna and swordfish, with a higher chance of tuna at lower levels. Thus this two fishes takes up two banking space and if the amount of tuna fishes you've caught is over 15, your combined income with the rest being swordfishes will be lower than a inventory filled with lobsters.
Harpoons weigh more than lobster pots. Therefore, when you run with a full baggage, your stamina decreases very fast. Also, a full baggage of lobsters weighs less than a baggage mixed with swordfishes and tunas.
When harpooning, you have to right click and left click on the "harpoon fishing spot" option, which is very irritating when fishing spots change constantly. Caging lobsters only require a click at the fishing spot.
When depositing your harvest, lobsters only require one right click on any of the lobstersin your inventory followed by "deposit all lobsters". When depositing a inventory with a mix of swordfishes and tunas, you have to repeat this process two times.
Therefore on the overall, lobster fishing is best until you reach a certain level of about more than 70 where you will be able to catch swordfishes at peace. On my next guide, I will share with you the timing I have made while lobsters fishing.