I’ve edited my previous question, you may need to look at what you dosing and feeding to find the source of the problem one of the items will be high in carbon
I feed a mix of frozen and pellets.
I do use GAC in a media cup but I am not thinking thats the reasoning for it.
Reef Roids
INGREDIENTS: MARINE PLANKTONS
Guaranteed AnalysisCrude Protein 60%
Crude Fat 20%
Crude Fiber 8%
Moisture 6%
Ash 6%
AquaVitro Fuel
fuel™ is a comprehensive carbohydrate, vitamin, amino acid, polyunsaturated fatty acid, and trace element supplement developed to address nutritional requirements commonly associated with corals. fuel™ contains ascorbic acid in a base of chlorella, which contains a rich assortment of amino acids and vitamins. The health benefits of chlorella are widely known and while spirulina, a similar algae, has been regularly used in the industry, aquavitro is the first to utilize the vastly superior chlorella. fuel™ is formulated to provide nutrients available from natural tropical reef waters.
Chlorella is a unique algae that grows in fresh water. It is extremely high in enzymes, vitamins and minerals, including the full vitamin-B Complex. It is over-flowing with unsaturated fatty acids, amino acids, and proteins. There are also vitamins found in Chlorella including: Vitamin C, pro-vitamin A (B-carotene), thiamine (B1), riboflavin (B2), pyridoxine (B6), niacin, pantothenic acid, folic acid, Vitamin B12, biotin, choline, Vitamin K, lipoic acid, and inositol. Minerals in Chlorella include: phosphorus, calcium, zinc, iodine, magnesium, iron, and copper. It contains a higher level of amino acids than spirulina and is FDA approved for use with ornamental fish.
Sera Marin Granules
Ingredients
fish meal, wheat gluten, wheat flour, wheat germ, Ca-caseinate, krill (6%), fish oil (containing 49% omega fatty acids), sea algae, brewers yeast, mannan oligosaccharides, spirulina, green-lipped mussel, stinging nettle, herbs, alfalfa, parsley, paprika, spinach, Haematococcus algae, carrots, garlic.
Analytical constituents
Crude Protein 54.8%, Crude Fat 7.8%, Crude Fiber 2.9%, Moisture 5.0%, Crude Ash 6.8%.
Additives
Vitamins and provitamins: Vit. A 30,000 IU/kg, Vit. D3 1,500 IU/kg, Vit. E (D, L-α-tocopheryl acetate) 60 mg/kg, Vit. B1 30 mg/kg, Vit. B2 90 mg/kg, stab. Vit. C (L-ascorbyl monophosphate) 550 mg/kg.
Emerald Entre and Frozen Brine does not mention anything about carbon.
I use the same food in all 3 of my tanks yet this is the only one with 0 nitrates. My 20g runs around 12-15ppm consistently with the same food and additives.