Without a doubt you are going to need a piece of software to take advantage of arbitrage opportunities as it is impossible to take advantage of them otherwise, however do you have the capital to pull this off? Arbitrage trading can be profitable but since the profit of each trade is low and you need to have several accounts in different exchanges then the amount of money needed to become profitable is incredibly high, so unless you can fulfill this requirement then you should forget about it for the time being.
I remember the time when it was possible to do without a bot for arbitrage trading, but now everything has changed and it is impossible for you to do without bots to get a profit. With such volatility in the cryptocurrency market, you can make a profit without wasting time on arbitrage trading.
Bots are quick monsters, they are near instant and that is why it is near impossible for people to make that kind of return. I know that it is not something that people want to hear but if you want to do arbitrage then you need to do it with a bot, otherwise you can't do it.
I know that people are using bots in trading anyway and you could make profit manually trading even though there are bots. However this is not the same, the chance to make a profit manually on trading is valid but the chance to find arbitrage chances are not valid. This is why we need to realize that we could only make a profit in the arbitrage world with a bot, not because there are no chances but because we wouldn't be fast enough.
Yes really true bot are really big monster on arbitrage, ever I faced what have you said I see order buy almost 20k$ and I want try arbitrage from dapp exchange to cex exchange market, without two minutes my coin credit to cex exchange market buy order was gone and I think not really understand how come higher buy order gone suddenly and all without any cent of order buy on price I want left. I think before arbitrage checking with how long buy order keep existing and see this possible or not for arbitrage.