Filter for 90 gallon

I am looking for another filter for my 90 gallon. As small as possible. I already have a sufficient one but i would like one more HOB. I had a 29 gal aquarium all inclusive and I tried using the filter from that but it wouldn't fit... What us the smallest/cheapest filter that would fit over this. The plastic top thing gets in the way

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That's what i have now. I wanted smaller for a second filter but still be able to fit...

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Any other suggestions

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