Agree. But the silicate dosing is apparently known to throw off the Hanna accuracy, and the suggestion is to use the Salifert or RedSea test kits in the interim.
So my assumption is that the nano tank still had a higher amount of silicates in the water due to previous dosing when this tank had dinos last (12 months ago) which led to the potentially inaccurate results for phosphates throughout. I do not have another explanation really how phosphates stayed at the same level even after a 50% water change.
More interesting though is the accuracy of the phosphates in the IM 150. Tested again this morning with Salifert and still seems to read 0. I also do not like the color tests but this seems rather straightforward here? Could still be a testing error, but 10ml, 4 drops and gently mix for 10 sec, then 1 level scoop and gently mix for 30 secs, seems hard to to do wrong actually.
Interesting though, nitrates are at 16 now (Hanna).
Time for reef roids (?).
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