Blocked hot tap only

[Dal Dhesi]

Hi there, i keep on getting white crystal like material blocking my hot water taps only. Started in the main showers then went onto Kitchen tap and then the bathroom taps. I have no water softner in the house and this only effects the hot water.

The substance looks like white dishwasher type crystals.

Any idea what could be causing this? I am now clearing the taps every 3-4 days now.