I agree with saffarinda. No idea what Tom is on about.
Interest is calculated DAILY and credited once a month.
Good idea to do as saffarinda suggests.
Not answering your questions but FYI - Goldman Sachs have launched a savings account in the UK called the Marcus, it pays 1.5% interest on balances up to £250,000 with no min/max monthly deposits.
1.5% is poor compared to many other options. As has already been stated, you could currently get 5% for up to £1500, and just have £500 going in each month, with at least £500 coming out just prior to that, so you keep getting 5% every month. Plenty of other options > 1.5%.