I have a 110 litre (30 USG) tank with an internal Juwel filter. All came as a package. The tank as just 4 danios as I am cycling it. They have been there for just over 3 days. The tank is testing as stable so more fish planned in a day or two. Now here’s the problem. This morning only 3 danios could be found. I found the other in the filter housing. He could not have got through the intake grill he is too big for that. Look at the photo there is a leaf against the grill it can’t get through. My only other thought is could he have jumped. On the ‘Net there have been others with fry getting in but my danio is bigger than that. The only thing I can think of is to put floss to the top of the filter housing. Personally I don’t like this filter but I have to live with it at least for the moment. Can anyone help?