Sounds like they need water rich in minerals.I'm still keeping them. I had my topic about some of mine. See link: https://www.fishforums.net/threads/celebes-halfbeaks.496437/
Nowadays, they're swimming with my Zoogoneticus tequila and Xenotoca lyonsi. Which makes a perfect combination. Well, mine don't always stay at the top. Mine do like to swim in all layers. Unlike my Dermogenys pusiila (pusillus)...
They also like to stay between those plants...
They're one of my favorite halfbeaks, btw...
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