It is a profitable trading tactics. Arbitrage is a method which looks for price difference in different markets and take profit from that price difference. However, it is next to impossible to manually control the trades in different markets/exchanges unless you keep funds in both of them! So arbitrage usually requires a big balance to start with as you will have to keep your accounts funded to reap that price difference benefit. Also you will need a bot account which will be connected with all your different exchange accounts and you can control them from one place! Then it is will become profitable venture for you! There is no algorithms that comes to play!