Shrimp tank advice
Hello there. I've recently bought a new aquarium, and am quite new to keeping aquatic life. The tank is a small desktop nano-cube, about 1.2 - 1.5 gallons, with an overhead lamp and a working filter. The tank has a large, single decoration of a curved "pillar row", I suppose I could best describe it, which sits in the center of the tank and forms a hollow, dark hiding place extending below the gravel outside it. Just behind this, in the curve, I've placed a large Lilaeopsis plant, and behind this in turn are a couple of fake plants which came with the ornament. I also have a green mossball in the corner of the tank. The tank temperature is around the mid 20s.
Today I bought four red cherry shrimp who have just been introduced to the tank. They seem to be reacting well - the two smaller, clearer ones which I assume to be males are darting about regularly and acting normally, whilst one female is resting at the back just waving her legs around herself and the other female is simply resting in a dark overhang of the decoration, moving only very slightly. This is my first concern - does anyone think this is strange or abnormal? My second question is - is this tank suitable for these shrimp? Are the plants good enough to hide in (for the Lilaeopsis) and feed upon (for the mossball)? Should I install a heater?
Also, I would like to ask for some advice about the future. I plan to have about 8 cherry shrimp in total in my tank, and would also like to have 2 golden apple snails as well. Will these two species work well together, and is the number of shrimp and snails I plan to get too much for a 1.2 gallon tank? Finally, what will the snails eat, and will they disrupt the shrimps' feeding?
Thank you for helping me! I know I'm probably seeming a bit silly asking all this, but I'm not very experienced in keeping tanks.