So I assume it's a hot, wet lowland tank...what about any of the tropical Australian petiolaris complex sundews (lanata, paradoxa, etc)?

D. adelae (lance leaf sundew) grows along-side D. schizandra and D. prolifera, so they should work well as companions.

Some Mexican butterworts might work as well, but be careful: some of them require (or very much prefer) a dry dormancy period.

{{gwi:546234}}D. prolifera

{{gwi:546235}}D. indica

{{gwi:546236}}D. spatulata

{{gwi:546237}}D. falconeri

{{gwi:546238}}D. paradoxa

{{gwi:546239}}U. gramminifolia

{{gwi:546240}}B. liniflora

I list these because they are truly living as companion plants in my ytopical setup.

Lycodium might be nice. I really like the temperate North American varieties that grow as companions to sarracenia in the wild.

There are several Southeast Asian forms. They are offered on eBay sometimes.
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