Back when I almost always had a few rams in my tanks, I'd begin with a group of young juveniles (I look for 2cm TL - note wild type fish are small, not the monsters you can find in many shops these days that have often been hormoned & hybridized ..... seriously fish has a great photo series on their M ramirezi profile), adding them to tanks with established plants & shrimp populations.
Most coexist quite fine with shrimp, mostly just taking some babies here & there - if you have a thick MC carpet you'll see the rams hunting as they sense the shrimp activity below but can't find the source ... mine never seemed to associate the young shrimp on plants/rocks with what they found so interesting below
My previous group began as 7 very nice electric blue juv's, they did great in the 90 x 45 tank, no losses until I somehow introduced a resistant strain of ich (I quarantine fish before adding to the main tank, I'm still at a loss how this began except with a possible carrier fish) ... of course by then I'd also spread it to both tanks as I sometimes move fish back & forth, use same syphon, nets, hands etc - long story short, 2 months later remaining fish & tanks were ich free
(successful tx was feeding metronidazole soaked food for a month! & frequent water changes, with attention to substrate vacuuming)
My electric blues were down to a trio, 2 male, 1 subordinate female .... I tried every combination possible, they existed but not thrived, I couldn't find more of same quality so finally gave them to a friend with a group
It's unusual that none of these 3 rams were happy as single fish - while they prefer groups, most do fine as singles.
Note the 2 males were v dominant, the surviving female had always been the least fish & seemed happy in that role, in addition these fish were notably shy
I spotted my present group at a local shop that had just gotten in various rams, gold, electric blue, German blue - I bought 5 from the "gold" group as they were a color morph I'd not seen before - still kick myself for not buying 7 but they were rather $$ & it's quite unlikely to get 5 same sex especially after choosing a size range of juveniles
Added these barely 2 cm fish to the 60 x 45 x 52 (tall), heavily planted tank, left lights etc off for the evening
Turned on lights next day, shortly thereafter see the ram group travel to one area, first fish dives & smacks the shrimp, second & third fish are bang, bang, then its shrimp for all (rams) - there were only a dozen or so shrimp culls in that tank so I left things as they were
Some time later I did a rescape & found a lone surviving big female who'd obviously figured out how to remain v well hidden
I mention height on this tank as this group of rams is quite outgoing & utilize every part of the tank in their "busyness"
Note I've never observed rams to be sensitive to large water changes, but as I do large frequent water changes, tank & tap parameters are always similar
Amano's are usually the toughest shrimp - waving off fish with their antennae (few fish seem to tolerate the touch, preferring to avoid/withdraw) or going underground & surviving fish attention that way - of course then they aren't algae crew either, though as you've observed Amano's love their fish food! more than algae anyway
What would you advise in a 600x450x450 100 or so ltr if I do go for it, 1xpair, 1male 2xfemale or two pair you reckon?
As with any dwarf cichlids I always recommend to begin with a group, then remove individuals which don't thrive .... I rarely need to remove rams from a group situation, even broody couples seem quite tolerant with no pysical damage inflicted - I'm not looking to breed so don't segregate pairs
If you follow Green Pekoe Pond you'll see a very nice ram pair (temporary boarders that seem to be a very well matched & dedicated pair)
