i just bought a 14g jbj nano it had been set for a yr and was established( kenyi trees about 8 from 1\2 inch to 5 inch tall and a torch,12lbs live rock), its been up and running for 2 weeks just added some fish now im trying to get rid of 2 damsels ($5 domino, blue yellow), any way i want a skimmer but dont know which to get would like a small one that would fit in the back but heard most dont work any help?