you might be able to get a couple of duiboisi which im pretty sure should be the 2n picture, normally 50 gallons would be preferable beacuse they like to be kept in numbers, first one would get way to big for your tank eletric blue, grows prolly 10 inches,
im not sure what the last one is kind of reminds me of a fuelleborni with the spots but im pretty sure its not, great fish though,
where are you getting these through?