I still cannot fully part with the idea of discus, but I also know that discus are demanding and I'm not that savvy, and the idea to kill perfect and pricy fish for nothing is not that appealing, so I'll talk myself out of it.
I know that angels do well in vertical tanks, I had angels before and they did well, so why not?
I like tetras, I like barbs, I like corys, I like kuhli loaches, I like botias, so I'll have to decide whether I go with corys or botias, I don't think there will be enough room on the bottom for both. I might want a pair or two of apistos or rams.
I want to make sure that the tank has enough oxygen on the bottom, I know it's a problem with vertical tanks. How do I achieve it? What filter would you recommend?
Discus are a hard fish to take the leap and get. They're expensive (especially because they're schooling fish) and compared to a lot of beginner aquarium fish they can be very easy to kill. It's hard.
However, don't let that disuade you. If Discus are something that you're interested in they're very feasible to care for.
I actually wrote an article today on this (https://freshwatercentral.com/2018/0...-expert-guide/
But basically if you truly want to keep Discus it's feasible. Just have some things figured out before you get them.
1) Try and stay away from wild caught Discus. I've found them to be more demanding of quality water conditions than home bred Discus. Personally I'm a fan of Kenny's Discus but off the top of my head I'm not sure where they come from. I believe they're imported from fish farms in south-east Asia.
2) Come up with a water change schedule before you get them. They're a lot of ways to cut down how long a water change takes w/ pumps etc.. If you have a sink near your aquarium it shouldn't be hard to build a system where you can do a 45 gallon water change in 15 minutes. Once you get it down to that w/ no bucket lifting etc. it makes Discus seem much less daunting.
3) Copy the breeder. That means ask them what water parameters they use and match them. Ask for a sample of food they use and copy it. Not changing stuff in the Discus' environment makes it much less stressful to have them.
4) Fully setup and cycle the aquarium and practice your water change system etc. Once you fully cycle your aquarium w/ ammonia for example try doing 40% water changes every day for 2 weeks (and keep putting in some ammonia to maintain your cycle). If it's too much then you can know that Discus aren't for you but if you're handling it fine and you have those 15 minutes then you know you can handle Discus.