I have a 12 Gallon Bookshelf aquarium with a 3 gallon refugium full of chaeto. Tank has been running for months. Ive dosed ammonia, added media and rock, from other established aquariums, and probably used 4 500mL bottles of Microbacter bacteria. My nitrates in the tank are high, but no matter what, the tank is always perpetually sitting at 0.25ppm of ammonia. It is absolutely ridiculous, and I just lost expensive stock because of this. The refugium has all of the used MarinePure, and the rock is in the tank. The refugium has chaeto with two lights that run at night. The flow is slow on this, and there are two nano HOBs on each side of the tank as well. Ive been trying to dose prime to protect livestock as well as doing water changes. The tank is sitting at 40ppm nitrates. There is bacteria enough for that many nitrates, but the ammonia will never go below 0.25. I have 8 saltwater aquariums set up, and this is the only tank I have ever struggled with cycling. Does anyone know what I can do? Im losing my mind over this.