in my opinion a prime 16 is good enough for rs nano, that’s what most of the people with that tank have, but if you want more light i dont think adding to cheap lights on the side is the solution, aesthetic wise on a nano is better just 1 light, plus you need quality not quantity, i think your best option is buy a used hydra 26 a ton on facebook marketplace at good price around 200 or (a 32 if you can find a good deal) then sell yours for around $175, you going to spend less at the end of the day, and your electricity bill going to be better than with 3 lights.