My preference is to cut off the spikes (right back as close as you can without damaging the plant) when they finish to allow the plant time to grow and strengthen ready for the next spike. You can sometimes get further bloomes on old spikes and many people like to leave them for that reason but I'm one of those who prefers to cut them back.
Just try and look after the plant and keep it healthy, watering them between once a week and once a fortnight is about right for my phals here in the UK and it's good to let them drain well just as you have been advised.
I favour using clear plastic pots (and they are often sold that way in the UK). By using those you can look at the roots to work out when they need watering, when the roots have just been watered you will see them go bright green. When they loose that colour (going more pale and silvery) and when there are no beeds of moisture inside the pot then it is time to water again.
Just look after them and with luck they will grow new spikes soon.