How do I remove aerator on kitchen tap?

[Postik]

All of the taps in my house have an aerator which is easily unscrewed for cleaning. However the kitchen one is spitting and blocked and it's the only one I can't unscrew.

The tap is an Ebb+Flo brand which can be seen here: https://www.toolstation.com/ebb-flo-castell-mono-mixer-kitchen-tap/p61716

There is a line near the end of the tap spout and I can't tell if this is where the tip is screwed on, or not. Alternatively, is it a "cache" aerator where I need a special key?

Some photos attached.

Thanks

 

[denso13]

Seems the tip is screwed on., this is supposed to be a replacement.

Ebb-and-Flo Castell Spare Parts CastellQ4 747F135203 1

Ebb-and-Flo Castell Spare Parts CastellQ4 747F1352031

www.tapmagician.co.uk