florida joe
Well-Known Member
Interesting info provided by Marco Lichtenberger
Frozen foods and thawing water
All foods used for fish and invertebrates contain phosphate (roughly 0.2-3% of its dry weight), but since you have to feed your animals, this input cannot be decreased at first glance. What you can do is keep the thawing water (that is not eaten anyway) out of the aquarium. Why all that rinsing work?
The thawing water of various frozen foods has been analysed with regard to its phosphate concentration (e.g. by Schwirtz). Contents between 0.74 mg/l (fish eggs thawed for 20 minutes) and 15.53 mg/l (mussel flesh thawed for 2 hours) were measured in 100 ml of RO water, in which about 3 grams of frozen food were thawed. Accordingly, in a 100 gallon tank fed with one un-rinsed 3 gram cube of mussel flesh the phosphate concentration is being raised by 0.0039 mg/l per feeding only by the thawing water. In 100 days without considering large water changes, this would correspond to a phosphate concentration of 0.39 mg/l, a concentration not healthy for corals, and the phosphates introduced by the actual mussel flesh are not even considered in this example. So, rinse your frozen foods!
Frozen foods and thawing water
All foods used for fish and invertebrates contain phosphate (roughly 0.2-3% of its dry weight), but since you have to feed your animals, this input cannot be decreased at first glance. What you can do is keep the thawing water (that is not eaten anyway) out of the aquarium. Why all that rinsing work?
The thawing water of various frozen foods has been analysed with regard to its phosphate concentration (e.g. by Schwirtz). Contents between 0.74 mg/l (fish eggs thawed for 20 minutes) and 15.53 mg/l (mussel flesh thawed for 2 hours) were measured in 100 ml of RO water, in which about 3 grams of frozen food were thawed. Accordingly, in a 100 gallon tank fed with one un-rinsed 3 gram cube of mussel flesh the phosphate concentration is being raised by 0.0039 mg/l per feeding only by the thawing water. In 100 days without considering large water changes, this would correspond to a phosphate concentration of 0.39 mg/l, a concentration not healthy for corals, and the phosphates introduced by the actual mussel flesh are not even considered in this example. So, rinse your frozen foods!
