Love these tanks, put the model in the search on this forum as there are some lovely examples.
Rather than putting a finger "up the hole" use a small bottle brush, or filter wool with the end of a teaspoon handle (kept only for the aquarium), or cotton buds. These will then remove any muck inside, to assist the impeller.
Warning with new filters, always check the internal contents as sometimes all the sponges etc are in sealed bags, thus will not work!
Many people take the Juwel filters out, as they find they are not very good. I bought a second hand Juwel Vision, with two external Ehiem filters included
More info here if you wanted to see it:
http
/www.fishforums.net/index.php?/topic/416184-new-project-juwel-vision-180-planted-journal/
read ya journal is great stuff
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