One of the cheapest solution to have clean bottle for aquarium fertilizers are medicicne bottles, available on local pharmacy. They cost 1-2€ each.

Here is one idea how to mount them on cabinet wall. Very useful in situation, you have very vew space in cabinet, like with nano tanks. Possible to mount them also on cabinet door.

Printer: MK2.5S
Noozle: 0.6mm
Material: PLA
Support: not needed
Brim: not needed

Enjoy and happy printing ;-)