Fish Getting Into Filter

[davec1960]

I switched off the internal filter this morning whilst I carried out a water change and gravel clean this morning. Before switching the filter back on I decided to change the floss so lifted the plastic top and found one of my sailfin mollies swimming around in the top of the filter box. This is not the first time this has happened I lost two rummynose tetras this way. I can't see anyway that fish can get into the filter other than by jumping on the top of it and falling through the finger hole in the centre of the lid.

I can't remember whether I say the molly yesterday or not so don't know how long she had been in the filter

Any ideas?

 

[Scott MacAdam]

I used to have a fire eel that would crawl into my external hanging filter and pop off the lid off and crawl in. I have no idea how or why but I always found the lid on the floor and his little head sticking out looking at me....

After that I covered the entrance and put rocks on top of it.