EI Dosing for Singapore Water - K, Ca, Mg, Fe, NO3 and PO4

[Growe]

For Planted aquarist living in Singapore, I checked and drew these conclusions (see PUB spec on potable water in ppm)

http://www.pub.gov.sg/general/Pages/WaterTreatment.aspx

Assuming water change happen once every week (30-50%), you are already dosing:-

Calcium - Singapore water has 50-120ppm (target 10-30ppm)
Potassium - need this as a key nutrients (target 20-3ppm)
Nitrate - Singapore water has 0.5 -15 ppm (target 15 - 20ppm).
Phosphate - Singapore water has < 0.1pp (target 0.5 - 2 ppm) So need to dose a little at water change
Magnesium - no mention in Spec, so may need to dose this
Fe - Very low in Singapore water - definitely a must dose.

Water from tap is

PH - 7
KH - 2 (need to buffer up to 3-4dh)
GH - 5 (measure of Ca and Mg)

So in conclusion, if you are hardworking aquarist who do water change and keep some tester kits to measure ph, kh, gh, NO3 and PO4. you just need to:-

1. No need to dose Ca (provided by Singapore PUB in form of CaCO3)
2. Dose Potassium Carbonate (kill 2 birds by adding K and buffer water to 4dh)
3. Dose Magnesium Sulphate (for Magnesium)
4. No need to dose nitrate if you have fish and shrimps (+ good cycled bio filter)
5. Dose Lushgro MICRO (this is for Fe and all other traces)

So theoritically, you need only Potassium Carbonate, Magnesium Sulphate and MICRO for PMDD and your plant will in great shape. Of course, testers helps to moderate the dosage.

Simple assumptions, make sense?

[eviltrain]

Yes. They way you put it make sense. But our water supplies comes from different water catchment area, reserviors, Newater . Plus we got different water treatment plant thru-out the island. There in just too much variables. Example, if u test five different location, eg, north , south, east, west and central. And by using the same test kit. You will see different results.
-bomb me if i'm wrong-

[|squee|]

It's good to use this as a guide. I looked up those values before and drew my own conclusions. Learnt something new though; didn't know iron was lacking in our waters.

[AquaZinYaw]

Thanks for sharing, Growe.

I stay in Tampines and this is my tap water parameter. I don't know about the tap water parameter from other places of singapore. Anyone tested before and can share?

pH=7.2, Ammonia=0, Nitrite=0, Nitrate=0, KH=2, GH=5, Phosphate=0.5

Cheers!

[TyroneGenade]

If you have a GH of 5 there is almost certainly Mg in it as Mg dissolves easier than Ca. You can test for the presence of Mg in solution (any chemists about in Singapore?).

Firstly, take a water sample and add enough HCl to acidify it (i.e. drive off all the carbonates). Then add ammonium carbonate. This will precipitate the Ca but NOT the Mg. Let the same stand pour off the clear solution into a new beaker. Now add sodium hydroxide. If Mg is present you should get a white jelly-like precipitate. Don't breathe too deep as the solution will release ammonia gas.

Any idea of the measure of Cl in the water? It needs to be about 20 ppm for good plant growth. This can be added as K, Ca or MgCl. I would not suggest adding MgSO4 as there is little need for SO4 in the aquarium. Enough S will enter the system with fish food.

tt4n