You should be fine in a 20 gallon tank. Is it a 20 gallon long or tall if it is a 20 gallon long they could live in there there whole life.
It is a 20 gallon tall and it is going to be planted
A planted tank is perfect but a pair should realy be in a 40 gallon, but they should be fine in a 20 gallon for a wile, i am not saying no you cant so give it a try and if they need more space than go for a 40 gallon and they will be able to live in the 40 gallon for the rest of there life and maybe breed.
Thanks, but i decided not to get rams I am getting dwarf gouramis.