You haven't been given any bad advice in the other forum, except the bit about needing salt (you don't).
Just differences in opinion
You don't say what filter you have. This will be the governing factor in how many fish you can keep.
It's probably the fluval 2 internal filter though.
Not the best filter in the world. It constantly blocks, and only contains a handful of media (which means smaller numbers of bacteria)
I thoroughly recommend you spend £50 (or get a second hand one even cheaper off ebay) and buy an eheim 2213.
These filters will repay that money with excellent reliability and performance. I have one still filtering as good as day one after 15 years. My fluval 2 lasted a month before I binned it.
With a large capacity quality filter you will have no problem keeping all those fish.
dont want to complicate it with too many fish that need different things!
I understand your concern, but
Corydoras and bristlenoses can be kept in the same tank no problem. They don't have different needs.
Corydoras (with exceptions) prefer cooler water (20-25C). Bristlenoses are quite flexible, and will be OK from about 22-29C.
The cardinals however prefer warm water (26-30C), but tank raised stock may be a bit more accommodating. Neons may be a better choice. Black neons are also worth thinking about (I prefer these).
Perhaps a good idea is to go ahead with the
Corydoras, and spend the money on a new filter in several months. Then you can add the bristlenose.
Choice of
Corydoras will also make a difference. Go for a small species such as
.
I hope I haven't confused you more!
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