I keep my breeding pair of German Blues in a 10g. The bottom of the tank is bare but there are loads of pieces of driftwood piled on top of each other to give hiding places and areas for spawning. I prefer this to having substrate as I can remove the driftwood between spawns to give the tank a thorough clean right down to the bottom glass so I know that there will be no contamination. German blues in particular like the water very clean so this is important. They also like their water soft and warm - I breed mine in about 28oC. Bolivians are more forgiving in water quality and like more "normal" tropical temperatures of about 25oC. I have never personally bred them as the group that I got to breed from were wiped out in a holiday power cut disaster last year, however they are lovely fish. Most of the time that you see bolivian rams in the shop they look very dull and grey, however they colour up beautifully as they mature. German blues tend to keep their colours slightly better in the shops hence they tend to catch your eye.
I don't know what prices you would pay in the US, but over here you can expect to pay £4-5 per subadult fish.
Sexing is difficult until mature. The german blue ram is easier in that firstly, the female has a blue iridescence over the black spot on her side whereas the male does not. Also, a mature male will normally have the first few black rays on his dorsal fin longer than the rest, whereas the females are all the same length. Once in breeding condition, the female will also get a bright pink/red belly.
With bolivians, the males tend to get longer extensions on their tails once mature. I found that they do need to be adult to see this though, and when buying from a shop the fish are usually subadult, so you're probably better getting a group with these to let them pair off themselves.
My german blues, I just picked out a pair at the shop and they bred for me. Some people prefer to again get a group and let them pair off themselves. Personal preference. If you're confident in your sexing then no reason to just get a pair at the start.
They are egg layers. They tend to lay their eggs on a flat(ish) part of bogwood in my experience. They choose this over a cave or a stone to spawn on. The eggs are tiny, like grains of sand. They hatch in a couple of days and become "wrigglers". The parents tend to move them to a different nest once at this stage. After another few days, they "take off" and become free swimming. This is when you start feeding the fry. I find baby brine shrimp too big for them initially, so I feed vinegar eels until they are big enough to take BBS. Some people find that their fry can take BBS straight away, but I have never had any success.
I separate the fry from the parents once they are about 2-3 weeks old so that the parents can recover and think about spawning again. The fry go into a partitioned 100l tank (partitioned into batches so that you aren't mixing a new batch with an older batch) and eventually wean the fry onto crushed tetra prima.
