Probably someone who figured he could make some money on cheaper carbon...
Your tank looks really nice and healthy! And so do the fish. The Trigonostigma look a bit like T. espei to me.. but hard to see in the video.
I'm curious how the Gobiopterus will do, when they turn up in the European trade they are usually in very poor condition so I never kept them, despite the fact it think they are awesome little fish.
Thanks. I was sold the Trigonostigma as Harlequi Rasbora which makes it a T. heteromorpha. This said I don't know for sure. I will take a picture later today and post it here. It is possible that it is a T. espei though. This is what I have read about the differences:
Source: https://www.seriouslyfish.com/species/trigonostigma-espei/
As for the Gobiopterus it is indigenous to the region where I am so they are pretty fresh and can be caught pretty easily although these ones I was told were bread in tanks. They are very funny to watch. They can open their mouth pretty wide. They also swim in schools but since they are only two they swim in schools with the Trigonostigma