I'd agree, the sennagal , gar, catfish and angle would be fine. Bush fish is another smaller oddball option that also would fit in .
I also agree that eel/bichir mix isn't a good one . Bichirs hunt at night by smell and will taste test whatever they bump into . Eels being so long and narrow with soft bodies tend to get gobbled up. I've even tried larger fire eels with same results.
As for channa I advise against that mix , channa are incredibly territorial even dawrf ones. They'll target and kill anything that the can and if the tank mates are to big or too tough to kill the channa becomes very shy and you'll never see it.
Also as mentioned the species your considering along with most dwarves are subtropical fish they can tolerate mid to high 20's for a short period of time (ie for their summer months) but if kept their long term and not given a winter cycle they'll become lethargic & develop infections they quite liturally melt away for sub tropicals the majority of the year should be below 20 and ideally they should get Winter temps dropping below 15 for the colder months.
As for order of adding the sennagal , gar, catfish and angle it shouldn't matter as none are overly aggressive. 55 g is fine for that mix but I'd try and ad 2-3 bichirs , they like the company of other bichirs they also arnt picky on species you could put several Senegal's or a mix of 2-3 similar size species and they get along just as well.
Hope that helps !
I also agree that eel/bichir mix isn't a good one . Bichirs hunt at night by smell and will taste test whatever they bump into . Eels being so long and narrow with soft bodies tend to get gobbled up. I've even tried larger fire eels with same results.
As for channa I advise against that mix , channa are incredibly territorial even dawrf ones. They'll target and kill anything that the can and if the tank mates are to big or too tough to kill the channa becomes very shy and you'll never see it.
Also as mentioned the species your considering along with most dwarves are subtropical fish they can tolerate mid to high 20's for a short period of time (ie for their summer months) but if kept their long term and not given a winter cycle they'll become lethargic & develop infections they quite liturally melt away for sub tropicals the majority of the year should be below 20 and ideally they should get Winter temps dropping below 15 for the colder months.
As for order of adding the sennagal , gar, catfish and angle it shouldn't matter as none are overly aggressive. 55 g is fine for that mix but I'd try and ad 2-3 bichirs , they like the company of other bichirs they also arnt picky on species you could put several Senegal's or a mix of 2-3 similar size species and they get along just as well.
Hope that helps !