Tropic Marin Pro-Reef Salt and PO4


Acropora Gardener
Dear all,

Quite a lot of us in the UK have recently discovered that TM Pro-reef salt contains phosphates that cannot be ignored. I opened a brand new tub a few days ago and tested PO4 using Elos high resolution test kit and it was between 0.046 and 0.092 mg/L. A friend of mine measured 21 ppb using his Hanna checker. There are many other similar readings.

When we approached to TM in Germany, one of the chief scientists confirmed that our readings were fairly accurate. It seems that the problem is not confined to a single batch or small number of batches of salt buckets. This means that whatever its batch number, if you purchased a Tropic Marine Pro-Reef salt recently, it may contain phosphates (some more than others).

To quote him: "Tropic Marin has been manufacturing sea salts for the aquarium hobby, with an almost unchanged formula, since 1964. In the early years of marine aquariums, phosphates were added to sea salts to improve their solubility. By choosing suitable raw materials, this could later be avoided. No phosphate has been added to Tropic Marin sea salts for almost 30 years.

Our sea salts contain natural salts as raw materials, which are purified to pharmaceutical quality. This pharmaceutical purity, of the raw materials, is one of the factors that makes the Tropic Marin sea salts unique.

However, when natural salts are processed to pharmaceutical quality, traces of phosphate can remain. The raw materials we use come mainly from sites of the dried up "œprimordial sea. For this reason, the phosphate concentrations in the pharmaceutically pure raw materials are roughly in the range of the phosphates found in the natural ocean. The Tropic Marin sea salts can therefore contain concentrations in the range of 0.01-0.09 mg / liter of phosphate. Our quality control ensures that raw materials with higher proportions are not used.
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Moving on Up
I don't see an issue with this. I've been using tropic Marin pro for years. I recently started giving Fritz a try. I tested that for phosphates and also got a reading around .03.

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Team RC
I have been fighting phosphate in my IM Lagoon 25 small fish load, light feeding, and I have algae problems I have only used Tropic Marine salt.