I am thinking of buying a Python water syphon as it is taking ages to do water changes on 3 tanks with buckets.
It doesn't look like I can remove the aerator on the tap so would either of these attachments work?
Almost any kind of adapter that you are looking to buy is going to need you to remove the aerator. There are ways of getting around that, but if it is your kitchen tap I don't think you want to do it...
Awesome! Take a pair of vice grips, put them on the aerator, use your other hand to hold the top of the faucet and take the aerator off. If you don't have vice grips then use pliers. If you don't have pliers, you could use a pickle jar opener.