I have a fluval evo evo 13.5 gallon and it's my first reef, looking back I should have waited and got a job and at least a 30-gallon before starting. I am looking for the best filtration system, I had bought a protein skimmer but it was a bio cube one and it was recommended by the local store and I didn't think and it don't fit in the back chamber. I have ceramic bio balls or whatever in the back and I use filter floss. I have bought Chemi Elite for phosphate but it's quite expensive for someone who don't have a job so I am looking for any recommendations as to what to do with filtration. I haven't tested parameters much either such as cal, mag or alk. I have been trying different salts and rightt now I am on tropic marin but I am also heard of people saying to use reef crystal but I ain't sure.