gouramis keep dying

ok so I had four gouramis I am now down to one the last two have died in the past week and I would really like to save the little guy I have left he is in a 40gal tank with two green spotted puffers a cory cat two rubber liped sucker fish and a some kind of catfish the puffers are the reason for the first of two gouramis dying they ate his back fin off and I qt him and moved him to the much more peaceful 10gal tank he lived a week and then died now the second of the two blue gouramis its stomach got really big like it swallowed a marble I thought it was going to have eggs but they need a male I just would like to know why its stomach got so big and btw he died this morning....
the little gourami in the tank with the puffers is doing good no bite marks no nothing keeping a close eye on should I move him to the 10 gal tank
please help I would like to not lose any more of the pretty little guys

 

Puffers are very aggressive fish generally not kept in a community tank. I have never kept them, but I believe they also need to be transitioned to brackish water as they mature. Sounds like gourami 2 had bloat, but I couldn't say why. I do think though that you will probably continue to lose fish unless you rethink your stocking.

 

id move puffers and use before new fish because it gives you a warning, if you go to a LFS then ask people there, or post here

 

aqadvisor is frequently wrong. Stocking is MUCH trickier than tank+fish+filter. In addition to having many of it's facts on species care/habits wrong, aqadvisor fails to take into account individual personalities of fish, the use of live plants, the amount/quality of filter media in said filters, and the feeding habits of the tank's owner. If you want to know if fish will go together/fit, ask the forum.
Also, green spotted puffers are brackish, and will eventually die if you continue to keep them in freshwater:
https://www.fishlore.com/aquariummagazine/nov08/greenspottedpuffer.htm

 

I used aqadvisor once and it helped more than some people on the forum, it may not always work but it says not to put puffers with gouramis, I think that is correct

 

That is correct, but should be a mute point as freshwater fish should not even be considered as tank mates for brackish fish. It's sort of like saying not to put goldfish and seahorses together.

 

The puffers are notorious fin chewers. I'd remove them and either rehome them or give them a brackish water setup. Also, I've been seeing a lot of posts about gourami bloat lately. I've never had that problem with any of mine; however, it raises some questions for me. Is it always females, or both sexes ?