Singapore tap water quality

[May&Bruce]

Back in August I took a tap water sample and had it tested by a reputable analytical laboratory in SG, as I wanted to know specifically what I was dealing with when mixing 700 litres of saltwater for our new 5 foot reef tank.

Here are the results:

Nitrate as NO3 = 4.00 mg/L

Phosphate as PO4 = <0.10 mg/L

Silicate as SIO2 = 4.26 mg/L

Residual chlorine as Cl2 = <0.10 mg/L

This is generally a little better than I was expecting. I thought that nitrate, phosphate and chlorine could all have been higher.

I do not know whether the Singapore water quality is the same across the island - this sample was taken from Bukit Batok.

[lightningstrike]

u shld hv all the info u need here.

http://www.pub.gov.sg/our_services/WaterWSHowBrought.aspx

[May&Bruce]

thanks lightning strike but with respect to the SG water works, they publish quite wide-ranging results. E.g. they state the following figures as being 'typical':

nitrate as NO3 = 0.5 to 15 mg/L

silicate as SiO2 = 3 to 12 mg/L

I was after something a bit more specific to where I lived. Anyway, as we already know we should not use tap water as-is: should use DI or RO/DI water.

[Gouldian]

thanks lightning strike but with respect to the SG water works, they publish quite wide-ranging results. E.g. they state the following figures as being 'typical':

nitrate as NO3 = 0.5 to 15 mg/L

silicate as SiO2 = 3 to 12 mg/L

I was after something a bit more specific to where I lived. Anyway, as we already know we should not use tap water as-is: should use DI or RO/DI water.

Hi May&Bruce,

DI or DeIonization is one of the proven way that removes impurites in water.

However DI medias are exhuasted very quickly, thus a RO membrane is addede before the DI media to filter our micro particles so that it will be less taxing of the DI medias thus RO/DI.

HTH

[May&Bruce]

Hi gouldian. Thanks, I am thinking of doing a DIY DI system as I can get the DI resin easy enough. Can't stand the thought of paying S$300 - S$400 for a system, so i reckon i can do one for less than $100-150

[Gouldian]

Great! Keep us posted.

If I remember correctly previously ANI & KATI medias are used but not sure about the modern DI methods.

Link

Edited December 2, 2005 by Gouldian

[May&Bruce]

yep, I understand that in the old days the anionic and cationic resins were in separate canisters, but these days mixed bed resin is used, which is simply a mixture of both.

Am thinking of doding a 3-stage system:

1. Fine particulate filter

2. activated carbon filter

3. mixed bed DI resin filter

Was not thinking of adding an RO stage due to the costs of the RO membrane. In contrast, 3.5 litres of mixed bed DI resin costs about S$45, and 3.5 litres should provide a lot of DI water.

[angelfish]

hi guys, do anyone know where to buy the DI mixed bed resin for replacement?

[gods_angel77]

good question angelfish i also don't konw where we can buy it form anyone?

[atos]

Hm..hm...May &...I realy doubt that there are any mixed bad column for pure DI water, Kati and Ani are still working, and I dont tink the mixed rsin will do the job.

regards

[May&Bruce]

Scottscentre Pte Ltd in Tuas. Our company buys it from them S$45 for 3.5 litres (mixed bed resin).

[Gouldian]

Thanks May&Bruce, I shall look forward to your DIY results.

Just a thought, where are you going to house the media?

I believe the container will be in considerable stress due to the high pressure created with the chamber.

[May&Bruce]

Gouldian...i am looking at using those inline filter cannsiters with the clear container that screws up into the blue top fixture, as are used for particulate filters, typically industrial use. Can buy them at Homely Hardware for S$35, but I want to find a cheaper source. They are mains pressure rated.

[Gouldian]

Gouldian...i am looking at using those inline filter cannsiters with the clear container that screws up into the blue top fixture, as are used for particulate filters, typically industrial use. Can buy them at Homely Hardware for S$35, but I want to find a cheaper source. They are mains pressure rated.

That's what I think will work too.

Guess you have had thought over it quite some time.

Do let us know of your progress!

Cheers!

[atos]

Some more informations May&Bryce, please , pictures, tech. spec etc?

[May&Bruce]

atos, will do - when I build it.

[atos]

OK...I keep your words

[May&Bruce]

i promise :-) have sourced the DI resin, and suitabel canisters, but I want to find a cheaper source for the canisters.

[ervine]

i'm confused.. why would you need a proper pressure rated canister? You mean the pressure of water from the mains thru the resin chamber is so high?

[May&Bruce]

mains water pressure rated, that's all. I was going to use a skimz FR, but I blew it apart with mains pressure water! Was able to glue it up and will use it for its intended purpose - FR, not as a mains pressure DI column