Phosphate is necessary as food for the health of corals. NSW PO4 is present at very low levels for, but from an unlimited source of supply.My vision in DSR is that the phosphate in a mixed reef tank should be measurable and that these corals best thrive between the values 0.02-0, 08ppm (measured with Redsea, Elos of Hanna testers). In the absence of phosphate you may experience one of the following signals:
- SPS, the coral tissue is slowly becoming lighter, transparent and eventually you get STN.(e.g.caliendrum)
- Faded colors which tend to grey/beige (Acropora species, except the pink and yellow)
- Leathers stop extendending their polyps, start growing algea and finally faling apart . (green sinulari sp. 02, green lobophytum sp. 06)
increasing PO4 level can be done wit a PO4 Additive (DSR PO4+)
How to start dosing PO4:
- Measuring PO4 with a realiable (low range) PO4 test. Use Redsea, Hanna, or elos PO4 test
-Start the DSR calculator, only the yellow cells are to be edited, and must therefore be checked.
- Fill the measured value in in the DSR calculator
- Check the water volume for the calculation, that should be the net volume in liters
- Check the action to stand on "correction values"
- Check the target value for PO4 (otherwise change this to your own liking)
- Read the to dose correction values in the columns "quantity" and "unit/raw material" (in ml).
You can increase the PO4 with up to 0,06ppm per day.
Phosphate is being buffered/bound in the system like many other substances. (Kh, iodide, strontium, iron)
This buffer can often prevent the PO4 dosage no longer being measurable within a day. Building of up phosphate in a system that has been PO4 deficient a long time can therefore take weeks (depending on the dose quantity and the substrate).
The best way is to work with a gradual daily dosage in combination with week corrections.
This goes like this,
day 1: measurement and do correction up to 0, 08ppm (or other desired value)
day 2 to 6: daily administration, the calculated correction dosage divided by 7 (0, 08ppm/7)
day 7 measuring and possibly correct and daily dosage to fit the defect or too much.
in essence, it is a matter of measuring every dosed 0,08ppm to pevent overdosing
Dosing can be done directly in the aquarium with an injection, pipette or right size Cup
Automatically daily dosing PO4 + is not recommended, unless you have a long-term and structural deficency (in term of months).
note1: determine that there is a phosphate deficiency by means of a low range test PO4. Stop the application of PO4 removers if that´s the case. Start with measuring and dosing PO4 after a week if it still is immeasurable.
Note2: the condition to be able to reduce nitrate using a carbon source is that Phosphate has to be present. Preferably at a level of 0.03-0, 08ppm. It sounds contradictory, but at a lower level (0,0-0, 02ppm) may help to dose phosphate to further reduce nitrate.
Note3: If you doubt whether you phosphate dosages do what they promise, or you are second guessing you PO4 test, you can do a 0.08 ppm DSR PO4+ dosing (only at zero measurement) and measure a half hour later. This should then at least be 0.08 ppm. This should only be done if you all above mentioned signals of low phosphate are recognized.