I have a waterbox 20 cube and I'm having some nutrient issues that weekly water changes aren't solving. I feed 1/4th of a frozen mysis cube per day and 1/4 teaspoon of reef roids per week, so the issue shouldn't be overfeeding. I do not have a skimmer, nutrient removing chemical media, or a refugium. My only source of export is weekly 10% water changes and an automatic filter fleece roller. Does anyone have recommendations for nutrient export in a tank this size? I would love tips on how to do a chamber 2 refugium or recommendations for a chamber 2 protein skimmer but HOB equipment would work. I already have the intank divider for chamber 2 if that can be used for anything. Chamber 1 has the fleece roller and Chamber 3 has my dosing and ATO stuff. I previously tried putting chaeto and a cheap submersible light in chamber 2, but the chaeto all died after a few weeks.