Tap Water TDM in various parts of Singapore

[teebs]

Hey peter, yeah i'm interested in the RO.DI unit.. I think I saw what you ordered on the marine depot website ....but I will monitor the usage of crystal pro.. if I need to change it soon again, I think I will make the switch as well and sell it off for other peeps with nano tanks rather than keep it.

The costs of the catridges are almost SGD65-70 everytime I change and if I need to change every alternate month all 3 cartridges or even just the 2 resin ones (SGD50 for both), it's certainly UNWORTH It.. for the amount of water I need.

Do let us know your preview on this product and if you wanna bulk order, put me on the list!

Waste water.. i'd use it to mop floor and clean toilet... ;P

Cheers,

Desi

Hi Desi, I believe the ones you saw at Marine Depot are the full size under sink RO/DI units. The one I'm getting is a portable RO/DI unit that has two outlets for drinking water and aquarium.

The portable one I'm getting is rated for a minimum of 1,500 gallons of water and the full size ones are rated for 2,500 ~ 3,000 gallons of water.

The DI unit is rated to produce 500 to 1,000 gallons of 0ppm water. This assumes that the water from the RO membrane is less than 20ppm.

[LaW]

Agree.

Wah looks so power...... why dun you do a bulk order for this one and help out some of the other bros here if this one is suitable.

LaW, what RO/DI are you using? care to share?

basically its a Kent marine Hi-S Maxxima. http://www.marinedepot.com/Kent_Marine_Hi_S_Maxxima_60_GPD_RO_DI_System_50_to_75_Gallons_Per_Day_RO_DI_Water_Filter_Systems-Kent_Marine-KM1431-FIRORDFS-KM1433-vi.html

fitted with a booster pump. i am also going to hook up another 2 stage cannister thats left lying in my store.

btw, if any one wants to get a RO/DI, visit bulkreefsupply.com

they have got a huge range at resonable price.

and just in case for those who don't know, RO membrane can last for a few years when taken care off. they are afraid of Cl ions, which can be reduced by use of carbon.

and if you think its a waste of water using RO, well... think again, how much $ on water waste Vs just DI resins.

furthermore, water are very cheap and could be recycled.

in the even of those people who feel bad about wasting the water, you can put another RO membrane on the waste water output so more water was saved instead of wasted.

btw Peter, dun drink too much RO water. our body need certain elements from it.

[teebs]

basically its a Kent marine Hi-S Maxxima. http://www.marinedepot.com/Kent_Marine_Hi_S_Maxxima_60_GPD_RO_DI_System_50_to_75_Gallons_Per_Day_RO_DI_Water_Filter_Systems-Kent_Marine-KM1431-FIRORDFS-KM1433-vi.html

fitted with a booster pump. i am also going to hook up another 2 stage cannister thats left lying in my store.

btw, if any one wants to get a RO/DI, visit bulkreefsupply.com

they have got a huge range at resonable price.

and just in case for those who don't know, RO membrane can last for a few years when taken care off. they are afraid of Cl ions, which can be reduced by use of carbon.

and if you think its a waste of water using RO, well... think again, how much $ on water waste Vs just DI resins.

furthermore, water are very cheap and could be recycled.

in the even of those people who feel bad about wasting the water, you can put another RO membrane on the waste water output so more water was saved instead of wasted.

btw Peter, dun drink too much RO water. our body need certain elements from it.

Wow...you are using high end stuff...

One easier way of producing less waste water is to use the 150GPD RO membranes. The waste water production is about 1.1 - 1.5L for every 1L of pure water produced. The 100GPD RO membrane that my unit comes with will produce ard 2L of waste water for every 1L of pure water.

BRS has many different RO/DI units at pretty reasonable prices but my price is cheaper than what BRS is selling at.

Just curious...why are you using a booster pump with your RO unit? I believe our house water pressure should be more than 45psi.

[LaW]

Wow...you are using high end stuff...

One easier way of producing less waste water is to use the 150GPD RO membranes. The waste water production is about 1.1 - 1.5L for every 1L of pure water produced. The 100GPD RO membrane that my unit comes with will produce ard 2L of waste water for every 1L of pure water.

BRS has many different RO/DI units at pretty reasonable prices but my price is cheaper than what BRS is selling at.

Just curious...why are you using a booster pump with your RO unit? I believe our house water pressure should be more than 45psi.

hi-end or not its all still basic cannister doing the same job. no need to get branded ones. waste of money. best to get those cheapest ones, they all perform equally.

for RO membrane to work properly, we need about 50-70PSI right? if im not wrong, from what i read from Dow Filmtec specification, optimal pressure is 70PSI. and for those who stays on higher level on flats, pressure was suppose to be lower. but i could be wrong. so do double check. you can also ask them to ship you a pressure guage to ensure it. i use the booster pump because it was a spare lying around, better to use it then letting it rot and rust.

and from what i know, pressure plays a part in the rejection ratio too.

[teebs]

hi-end or not its all still basic cannister doing the same job. no need to get branded ones. waste of money. best to get those cheapest ones, they all perform equally.

for RO membrane to work properly, we need about 50-70PSI right? if im not wrong, from what i read from Dow Filmtec specification, optimal pressure is 70PSI. and for those who stays on higher level on flats, pressure was suppose to be lower. but i could be wrong. so do double check. you can also ask them to ship you a pressure guage to ensure it. i use the booster pump because it was a spare lying around, better to use it then letting it rot and rust.

and from what i know, pressure plays a part in the rejection ratio too.

Yup, for the RO membrane to start producing pure water, water pressure needs to be between 45 - 65 psi.

I'm not sure whether this is still the case for all HDB flats though. I know for old flats, the upper levels have lower pressure than th elower levels but the water pressure in my flat seems to be ok.

[LaW]

Yup, for the RO membrane to start producing pure water, water pressure needs to be between 45 - 65 psi.

I'm not sure whether this is still the case for all HDB flats though. I know for old flats, the upper levels have lower pressure than th elower levels but the water pressure in my flat seems to be ok.

then you can do without a booster pump.

i believe booster pump is for some cases. im currently trying to find a pressure guage for the RO vessel. i heard i can find it in jalan besar. but that road is so long,finding it without proper address is time consuming. hope those who knows can enlighten me.

[FuEl]

A very good article on RO & DI units. The last section highlights how to extend the life of your DI resin.

http://www.aquarticles.com/articles/saltwater/metelsky_water%20qualityhtml.htm

I don't use RO, since Singapore tapwater is already of potable standard. RO is more for areas with non-potable water, with the need to filter out pathogens from the water.

The TDS reading of the tapwater at my place is around 100+. I only got a DI unit mainly to reduce my diatom problems due to silicates. Even before I got a DI unit, I was already raising shrimp and fish larvae using water straight out of the tap. Corals, including SPS, did well too with Rowaphos running in a FR. The only additive I used was anti-chlorine since local tapwater has chloramine added.

I've always wondered if it is necessary to use such pure water. No commercial salt mixes to date even match the exact properties of seawater. Even metals in the so-called best salt mixes are often hundreds or thousands the concentration of the levels found in NSW. What is the point of using such pure water when you are simply adding excess elements back into your tank when you mix such water with the "perfect" salt?

In my honest opinion, as long as you run carbon blocks to remove potentially harmful inorganics and resins to absorb the unwanted phosphates and silicates, the water should be good enough even for the most demanding reefers. I do not see the point of wasting so much water through RO. If you need a lot of water purified, go for industrial DI units. Those are way more economical compared to those aquarium sized units.

I do not know the cost over time of a properly designed DI unit versus a RO unit but given a choice of saving money and saving water, I choose to save water.

[FuEl]

http://www.spectrapure.com/St_di_systems.htm

DI technology is more advanced now. What many people are unaware of is that there are many grades of DI resins. If the resin grade is poor, it will get exhausted very quickly.

A link which explains the different resin grades.

http://www.industrialwaterequipment.ie/ion-exchange-resin.html

[teebs]

The cost difference between using a pure DI unit and a RO/DI unit can be quite substantial even in the short to medium term. A lot depends on the amount of pure water you require and also the initial and replacement costs of the catridges.

Using the RO/DI unit that I'm getting as a guide to compare to the current Crystal Pro DI unit that I'm using, the cost difference is still pretty substantial.

5 stage 100GPD Portable RO/DI unit with replacement catridges (1 sediment, 2 carbon, 1 MB400 DI catridge) and 1.5 Lb of replacement MB400 DI resin.

1.5Lb of DI resin is sufficient for 4 refills.

1 DI catridge is rated for minimum 500G of pure water, sediment and carbon catridges are rated for between 1,500 to 2,500 gallons.

In my case, my set is rated to produce at least 3,000 gallons (~12,000L) of pure water. Cost is SGD 400 for this set.

Current Crystal Pro unit

Cost SGD 198 (AM website)

Replacement Hi Cap DI Catridge - $30 each

Replacement Carbon Catridge - $24 each

Water used for top up of evaporated water is approx 20-30L per week. Using NSW from Iwarna for water changes.

Currently, Crystal Pro unit lasts about 2 months before I need to change the DI catridges. Last replacement was before CNY during the AM CNY promotion.

Current TDS reading of the water generated by the Crystal pro unit is 95ppm.

Assuming:

1) Change both DI catridges every 2 months, 1 year spending on DI catridges: $360

2) Change Carbon filter every 6 months, 1 year spending on Carbon filter: $48

3) Total cost for 1 year: $198 + $360 + $48 = $606

4) Total DI water produced: 240L based on 30L weekly over 8 weeks

5) Annual DI water usage: 30L/week x 52 weeks = 1,560L

Assuming waste water from Ro/DI unit is drained away:

1) Assuming 120L of pure water produced per month, waste water production at 2.5x of pure water production: 300L/month or 75L/week

2) SP Services Water Rate: $1.17/cu m + $0.28/ cu m = $1.45/cu m

3) 1 cu m of water = 1,000L of water

4) Annual waste water cost = 75L/week x 52 weeks /1000 x $1.45 = $5.66

[teebs]

http://www.spectrapure.com/St_di_systems.htm

DI technology is more advanced now. What many people are unaware of is that there are many grades of DI resins. If the resin grade is poor, it will get exhausted very quickly.

A link which explains the different resin grades.

http://www.industrialwaterequipment.ie/ion-exchange-resin.html

The best DI system I have seen is from Aqua Technic. They use two seperate Kati and Ani De-ionizers in this system. According to them, 1L of Kati/Ani De-ionizer is able to produce 100G of DI water.

[LaW]

The cost difference between using a pure DI unit and a RO/DI unit can be quite substantial even in the short to medium term. A lot depends on the amount of pure water you require and also the initial and replacement costs of the catridges.

Using the RO/DI unit that I'm getting as a guide to compare to the current Crystal Pro DI unit that I'm using, the cost difference is still pretty substantial.

5 stage 100GPD Portable RO/DI unit with replacement catridges (1 sediment, 2 carbon, 1 MB400 DI catridge) and 1.5 Lb of replacement MB400 DI resin.

1.5Lb of DI resin is sufficient for 4 refills.

1 DI catridge is rated for minimum 500G of pure water, sediment and carbon catridges are rated for between 1,500 to 2,500 gallons.

In my case, my set is rated to produce at least 3,000 gallons (~12,000L) of pure water. Cost is SGD 400 for this set.

Current Crystal Pro unit

Cost SGD 198 (AM website)

Replacement Hi Cap DI Catridge - $30 each

Replacement Carbon Catridge - $24 each

Water used for top up of evaporated water is approx 20-30L per week. Using NSW from Iwarna for water changes.

Currently, Crystal Pro unit lasts about 2 months before I need to change the DI catridges. Last replacement was before CNY during the AM CNY promotion.

Current TDS reading of the water generated by the Crystal pro unit is 95ppm.

Assuming:

1) Change both DI catridges every 2 months, 1 year spending on DI catridges: $360

2) Change Carbon filter every 6 months, 1 year spending on Carbon filter: $48

3) Total cost for 1 year: $198 + $360 + $48 = $606

4) Total DI water produced: 240L based on 30L weekly over 8 weeks

5) Annual DI water usage: 30L/week x 52 weeks = 1,560L

Assuming waste water from Ro/DI unit is drained away:

1) Assuming 120L of pure water produced per month, waste water production at 2.5x of pure water production: 300L/month or 75L/week

2) SP Services Water Rate: $1.17/cu m + $0.28/ cu m = $1.45/cu m

3) 1 cu m of water = 1,000L of water

4) Annual waste water cost = 75L/week x 52 weeks /1000 x $1.45 = $5.66

now we are seeing some datas

[teebs]

now we are seeing some datas

Data is always necessary...At the very least it will show proof of what you are talking about.

Anyway, to add on, a couple of months back I had a discussion with a supplier of DI resins in USA.

And what he told me was that for a catridge of DI resins like the Crystal Pro unit, the amount of resin in it is approx 1.5lb and this amount of MB400 resin is able to absorb 5,100ppm gallons of ions before it is exhausted.

So to calculate how long your Crystal Pro DI catriges can last (Assuming they are using 1.5Lb MB400 resins in each catridge), the formula is:

5,100ppm x 2 catridges/ TDS reading of your tap water = how many gallons of DI water that can be produced. To convert gallons to Litres, multiply by 3.8.

In my case, it will be:

5,100 x 2/ 165 (TDS of my tap water) x 3.8 = 235L of DI water.

[FuEl]

Those who wish to order DI resin can pm shootsimon. 1L is only around $10+ IIRC.

[LaW]

Data is always necessary...At the very least it will show proof of what you are talking about.

Anyway, to add on, a couple of months back I had a discussion with a supplier of DI resins in USA.

And what he told me was that for a catridge of DI resins like the Crystal Pro unit, the amount of resin in it is approx 1.5lb and this amount of MB400 resin is able to absorb 5,100ppm gallons of ions before it is exhausted.

So to calculate how long your Crystal Pro DI catriges can last (Assuming they are using 1.5Lb MB400 resins in each catridge), the formula is:

5,100ppm x 2 catridges/ TDS reading of your tap water = how many gallons of DI water that can be produced. To convert gallons to Litres, multiply by 3.8.

In my case, it will be:

5,100 x 2/ 165 (TDS of my tap water) x 3.8 = 235L of DI water.

thats pretty accurate for your estimation of 240l and my 200l

[MarcoVan]

A very good article on RO & DI units. The last section highlights how to extend the life of your DI resin.

http://www.aquarticles.com/articles/saltwater/metelsky_water%20qualityhtml.htm

I don't use RO, since Singapore tapwater is already of potable standard. RO is more for areas with non-potable water, with the need to filter out pathogens from the water.

The TDS reading of the tapwater at my place is around 100+. I only got a DI unit mainly to reduce my diatom problems due to silicates. Even before I got a DI unit, I was already raising shrimp and fish larvae using water straight out of the tap. Corals, including SPS, did well too with Rowaphos running in a FR. The only additive I used was anti-chlorine since local tapwater has chloramine added.

I've always wondered if it is necessary to use such pure water. No commercial salt mixes to date even match the exact properties of seawater. Even metals in the so-called best salt mixes are often hundreds or thousands the concentration of the levels found in NSW. What is the point of using such pure water when you are simply adding excess elements back into your tank when you mix such water with the "perfect" salt?

In my honest opinion, as long as you run carbon blocks to remove potentially harmful inorganics and resins to absorb the unwanted phosphates and silicates, the water should be good enough even for the most demanding reefers. I do not see the point of wasting so much water through RO. If you need a lot of water purified, go for industrial DI units. Those are way more economical compared to those aquarium sized units.

I do not know the cost over time of a properly designed DI unit versus a RO unit but given a choice of saving money and saving water, I choose to save water.

^ +1

I did what Fuel said before for my ex 1ft nano cube. Absolutely no problem!

Happy Reefing,

Marc J.

[teebs]

Just for information, this is the water quality from our waterworks from PUB website:

[pandagold]

could buying distilled water ( those in supermarkets ) have the same effect as RO or DI, minus the hassle of PO & DI ?

[teebs]

could buying distilled water ( those in supermarkets ) have the same effect as RO or DI, minus the hassle of PO & DI ?

yes, distilled water is the same as RO/DI water. The NTUC brand of distilled water that I used previously had a TDS reading of 1-3ppm so it is definately useable.

However, cost wise, buying bottles of distilled water is going to be more expensive than using RO/DI in the long run. Of course if you have a nano/pico tank, then it doesn't make sense to get a RO/DI unit either.

[jackywongto]

could buying distilled water ( those in supermarkets ) have the same effect as RO or DI, minus the hassle of PO & DI ?

Hi bro, you can use either distilled or RO/DI.

But as to which one is more of a hassle ... a bit debatable.

using RO/DI - you can get the water as and when you need it. do not have to worry about stocking bottles of water. But need to change resins and media from time to time.

Leveraging on distiiled water which is about 45 cents per 1.5l during special offer days, it could be cheaper with no startup cost. But you would need to carry cartons of bottled waters back from supermarket to your home and also find place to stock them up. Then for water change,you will need about 7 bottles for a 20gallon tank. If you do it weekly, then you need about 28 bottles per week and you still need to buffer some bottles for topping up daily.

This should give you a good idea of how many bottles you need. (unless if you are ordering those commercial distilled water - large large container ones that are being sent to your place.)

hope this help.

[Zhang]

AMK, central 3, Reading is 100