trying to make a refugium

so i have a 40 gallon tank give or take (i got it from a friend who doesn't know the exact size) and recently had a colossal nitrate spike. After some research i came upon refugium tanks below the main tank as a way of keeping the chemicals more balanced. I also don't have a protein skimmer. Would it be possible to turn an old ten gallon tank into a refugium for the protein skimmer and also have it be a copepod breeding area? Also if i were to try and change the 10 gallon into a refugium how much work would it be to start up? What materials would be necessary to do it? And if i wanted to make half a protein skimmer and half a copepod and amphepod fuge could i just use a tank divider that i could buy at petsmart or petco?



Thank you in advance and if i wasn't the clearest i'm sorry i'm new here. If there's any more information anyone needs just let me know!