Hello, I have an 16 gallon AIO saltwater aquarium and I find that my nitrates are abnormally high, I have been doing 15% water changes on my tank and I recently switched to 30% water changes. However, these are doing nothing. Is there another way to lower nitrates in a reef? I don’t have room for a refugium. I use Salifert test kits for nitrates and phosphates and I haven’t seen any change in the tests for over 2+ months. I just have a cleaner shrimp, 2 clownfish, and a goby. If any help is provided, it would be appreciate. Thank you.