Tap water quality, is it really that bad?

The_Alchemist · 09/06/2006, 11:36 AM

Hi,

I've been keeping a 230 gal reef tank for over a year now, and haven't had any major problems..

I have been reading alot about people investing in ro/di systems to purify water, and while i'm considering investing in one, i'm not convinced that its worth it.

so far i haven't seemed to have any algae problems, and water pramaters aren't bad and so corals and fish seem to be well and happy.

I have heard that the water plant close to where i live is one of the most advanced in the country, and so given that fact is it still worth getting an ro/di unit when i aerate my tap water for 12 hours and add water conditioner (prime) prior to water changes?

here are some of the water parameters i obtained for the tapwater for my area.. does anyone know whether they are good or bad..

thanks in advance.

Test Typical value Unit
pH
90% of values between 7.5 and 8.5
pH units

Alkalinity (total)
35.8
mg/L as CaCO3

Colour (true)
2.38
Pt-Co units

Turbidity
0.47
NTU

Fluoride
0.91
mg/L

Total Hardness
39.6
mg/L as CaCO3

Iron
0.033
mg/L

Manganese
0.010
mg/L

Aluminium
0.033
mg/L

Copper
0.018
mg/L

Lead
0.0004
mg/L

(nitrates 0, ammonia and phosphates near 0)

drummereef · 09/06/2006, 12:03 PM

Algae problems aren't neccessarily the only issue with tap water. There are many other metals and other properties of the water that make it not so great for aquariums. When you get to the DI stage it should basically be reading 0 tds. 0 total disolved solids. Pure. You can't go wrong with pure.

seattlerob · 09/06/2006, 12:14 PM

While many of those readings look very low, it's my understanding that things like copper, lead, aluminum, etc will build up over time. So, even though you've been using tap water for over a year now, it's possible at some point in the future this 'build up' of metals will lead to trouble. And, it's likely you'll see the results but will be unsure of the cause.

The better test would be a TDS reading of your tap water. As drummerreef mentioned, RO/DI will give you very close to 0 tds. I just purchased the COM-100 TDS meter, and here are my results just to give you an idea of what RO/DI can do:

my tap water (seattle): 38ppm tds
after RO: 19ppm tds
after RO/DI: 0.6ppm tds

So, the RO water is 2x 'purer' than tap, and the RO/DI is 60+x 'purer'. Also, not sure where you're located, but I believe 38ppm out of the tap is pretty low compared to some parts of the country.

hth,
rob

RichConley · 09/06/2006, 12:24 PM

seattlerob, why would they build up? Thats what water changes are for.

The issue with tap water isnt neccessarily the cleanliness. Its the lack of consistency. The water company flushes a main down the street, and suddenly you have rust, high ammonia, etc. You can go from the 35tds I had, to 500+ in a matter of a couple hours. It rains, and you get washoff in the resevoirs.

FWIW, there are plenty of heavy metals in our salt mixes.

RichConley · 09/06/2006, 12:27 PM

SeattleRob, if you're only going from 38 to 19 through your RO membrane, either 1) Your TDS meter is bad, 2) your RO membrane is bad.

RO membranes should show between a 90 and 99% rejection rate.

So with TDS of 38 going out, you should get between 0 and 3 depending on your membrane. You should always get 0 out of the DI.

In my new apartment, I get 65 tds on the tap. I get about 2-3 coming out of the RO unit, and 0 coming out of the DI.

If 19 is going to your DI, you're going to be replacing it every 2-300 gallons, IIRC.

HowardW · 09/06/2006, 01:08 PM

The TDS in our tap water here is over 350 and our water also contains chloramines, phosphates, silicates, and all kinds of other nasty stuff. I wouldn't even consider doing water changes or topping off with our tap water.

Some parts of the country however have very low TDS readings on their tap water, I heard one guy say his tap water TDS was 19

outy · 09/06/2006, 02:19 PM

mine was 18 yesterday kind of stays around 21

i still have a ro/di and would not run without one.

scooters reef · 09/06/2006, 02:30 PM

Quote:

Originally posted by RichConley
seattlerob, why would they build up? Thats what water changes are for.

But tap water would also be added as top-off. The levels would slowly rise. A subsequent water change would drop them, but not all the way down to what was in the tap water itself because the concentration in the tank is already above that. Through time it would still build up. No clue how long until it was lethal to anything, but it would accumulate.

Paul B · 09/06/2006, 03:47 PM

I used tap water in my reef for about the first twenty five years with no problem. Then the town put zinc orthophosphate in the water supply to control corrosion in the pipes. I lost most of my very old corals in a matter of hours. I had to buy 100 gallons of distilled water at a supermarket on Sunday night. Now I have a RO/DI
Although my tap water is fine, sometimes it changes.
Paul

cheeks69 · 09/06/2006, 04:04 PM

I have used tap water for 5 years with no problems at all. I have never tested it just add a conditioner and I'm done. I realize in most areas of the country the water quality is real bad and an RO is a must but for me tap it is !

Here's a couple of photos:

melev · 09/06/2006, 04:04 PM

The metals aren't flushed out of the system via water changes, and often are trapped in the sandbed of your tank.

If your tank is healthy and happy, you may not need to change your system. Where I've lived, it was necessary to get an RO/DI for my tanks.

thor32766 · 09/06/2006, 05:19 PM

wow sweet tank, all i use is a carbon block drinking filter on my tanks

AZDesertRat · 09/06/2006, 06:02 PM

Before even considering Tap Water I would suggest two things. Obtain a copy of your water utilities water quality report and study it closely. Next make it a point when you ask for the report to tell the person you are a salt water reef keeper and see if they will refer you to either one of their staff who also keeps fish or corals or to a plant supervisor or senior operator. Explain the same to them and listen to their recommendations. Ask how often they change sources or blends of water or change treatment techniques or chemicals. You might be surprised at how often your tap water changes in a weeks or months time. After storm events or seasonal changes water changes dramatically and thats a bad thing for tank stability.
I would never ever recommend tap water to a reefkeeper no matter what part ofthe world they are in simply because it does not have the stability that owning your own RO/DI unit has. You know each time you use it what the water quality is.
Things that are safe for human consumption and meet all state and federal regulations may not be safe for corals and things like metals do not go away but stay in your system and build up forever until your system crashes and leaves you scratching your head as to why.
Carbon does almost nothing for your tap water except adsorb chlorine and volatile organic chemicals and thats only if its a good one and is changed often.

BHF · 09/06/2006, 06:39 PM

I dunno, hell, I'm a newbie, but I'll fall back on an well respected expert who states:

Quote:

My view is that [pollutants in tap water] is actually insignificant compared with all the other contributing factors affectinging the makeup of your system's water...Compared with other contributing factors in marine systems, ordinary treated tap water is not typically a major source of concern in terms of added nutrients, pollutants, and/or metals...Marine Aquarists with reef systems and especially poor city or well water may find small home-scale reverse osmosis (RO) and deionization (DI) units of definite benefit, and more economical than the most basic catridge type conditioners. However, I suggest that even finicky reef types take a hard look at the quality of their skimmers and their feeding and supplementing habits before deciding that RO/DI will be their water-quality panacea. It's very often only a small part of the solution.

AZDesertRat · 09/06/2006, 06:53 PM

Yes but ask that expert if they use a RO/DI and I would almost bet they say yes. My tap water TDS exceeds 700 all the time and can reach over 1000 ppm TDS at times. In the West and Southwest thats common and I sure don't want that in my reef system. I would have to agree with your expert though, water is the single largest component of a reef system and is the most important part of it so why not provide stability by using RO/DI. I have operated and supervised many treatment plants and water systems over the years and none has the stabiity day to day that a little inexpensive RO/DI unit has. Your expert may know corals and fish but he is a littl lacking on water quality knowledge if I may say so.

BHF · 09/06/2006, 07:06 PM

::shrug::

I'm sure Bob Fenner has picked up enough here and there to get by. To each their own, but as Cheeks pretty clearly shows, you can do just fine with tap water.

AZDesertRat · 09/06/2006, 07:08 PM

Bob is a personal friend and I can always disagree with him. It makes for some fun conversation. If you ever get the chance to spend some time with him I encourage you to do so, the guy is hilarious!

deadfish2 · 09/07/2006, 05:23 AM

I use the tap water filter and stress coat for my water. Everything fine and I got no alage for my snails.

seattlerob · 09/07/2006, 08:09 AM

Rich: yeah, I think you're right. I just purchased both the RO/DI & TDS meter thru purelyh2o.com. The RO/DI is about 1 month old, the TDS meter I just received this week. I rechecked the RO/DI reading this morning and it was 0.3ppm. I will recheck the RO output again this afternoon.

Hoping neither my TDS meter or RO membrane is bad. But if I test the same, I'll circle back to purelyh2o.com & see what Bryan thinks.

Thanks,
Rob

Quote:

Originally posted by RichConley
SeattleRob, if you're only going from 38 to 19 through your RO membrane, either 1) Your TDS meter is bad, 2) your RO membrane is bad.

RO membranes should show between a 90 and 99% rejection rate.

So with TDS of 38 going out, you should get between 0 and 3 depending on your membrane. You should always get 0 out of the DI.

In my new apartment, I get 65 tds on the tap. I get about 2-3 coming out of the RO unit, and 0 coming out of the DI.

If 19 is going to your DI, you're going to be replacing it every 2-300 gallons, IIRC.

RichConley · 09/07/2006, 08:38 AM

Quote:

Originally posted by seattlerob
Rich: yeah, I think you're right. I just purchased both the RO/DI & TDS meter thru purelyh2o.com. The RO/DI is about 1 month old, the TDS meter I just received this week. I rechecked the RO/DI reading this morning and it was 0.3ppm. I will recheck the RO output again this afternoon.

Hoping neither my TDS meter or RO membrane is bad. But if I test the same, I'll circle back to purelyh2o.com & see what Bryan thinks.

Thanks,
Rob

Rob, it may be seated incorrectly or something.

Were you just checking right after it started up? TDS can be much higher for the first gallon or two.

seattlerob · 09/07/2006, 09:32 AM

Rich: when you say seated incorrectly, are you talking about the RO membrane? If so, I can check that. Honestly, when the unit arrived, I did not open any of the canisters to check anything. A couple were a bit loose & leaked, but I just hand tightened them until the leaks stopped.

I have a DI bypass and I was measuring TDS of the water com ing out of the bypass. In hind sight, I did not let the water run at all before taking the reading. I just filled up a tupperware with about 2 ounces & then took the reading. When I get home, I'll let it run & discard the 1st gallon or two & then take the reading. I'll bet you're right on the money & hope the TDS reading will be much lower. Either way, I'll post back my results & appreciate your comments

rob

AZDesertRat · 09/07/2006, 09:51 AM

Use a very clean drinking water glass that has no dishwasher soap residue or any visible spotting on it for a sample container. Always triple rinse with DI water after each sample and again when you are done with it. Tupperware and other plastics can give bad readings.

seattlerob · 09/07/2006, 09:53 AM

AZDesertRat: thanks for the advice! Appreciate it....learn something new everytime I come here

Rob

Tobman · 09/07/2006, 09:56 AM

IMHO, really good RO/DI units don't cost that much (esp. compared to all else we spend) and are easy to use. It takes a bit longer to obtain the make up water, but you can do it while you sleep.

Just get an RO/DI unit and the question is moot.

RevHtree · 09/07/2006, 10:06 AM

My tank has NEVER seen a drop of RO/DI water. It has been running for about 3 years now. My water is not that bad in my area though.

09/06/2006, 11:36 AM	#1
The_Alchemist Registered Member Join Date: Aug 2006 Posts: 11	Tap water quality, is it really that bad? Hi, I've been keeping a 230 gal reef tank for over a year now, and haven't had any major problems.. I have been reading alot about people investing in ro/di systems to purify water, and while i'm considering investing in one, i'm not convinced that its worth it. so far i haven't seemed to have any algae problems, and water pramaters aren't bad and so corals and fish seem to be well and happy. I have heard that the water plant close to where i live is one of the most advanced in the country, and so given that fact is it still worth getting an ro/di unit when i aerate my tap water for 12 hours and add water conditioner (prime) prior to water changes? here are some of the water parameters i obtained for the tapwater for my area.. does anyone know whether they are good or bad.. thanks in advance. Test Typical value Unit pH 90% of values between 7.5 and 8.5 pH units Alkalinity (total) 35.8 mg/L as CaCO3 Colour (true) 2.38 Pt-Co units Turbidity 0.47 NTU Fluoride 0.91 mg/L Total Hardness 39.6 mg/L as CaCO3 Iron 0.033 mg/L Manganese 0.010 mg/L Aluminium 0.033 mg/L Copper 0.018 mg/L Lead 0.0004 mg/L (nitrates 0, ammonia and phosphates near 0)

09/06/2006, 12:24 PM	#4
RichConley Registered Member Join Date: Sep 2004 Location: Bostonian in Chicago going to DC Posts: 9,908	seattlerob, why would they build up? Thats what water changes are for. The issue with tap water isnt neccessarily the cleanliness. Its the lack of consistency. The water company flushes a main down the street, and suddenly you have rust, high ammonia, etc. You can go from the 35tds I had, to 500+ in a matter of a couple hours. It rains, and you get washoff in the resevoirs. FWIW, there are plenty of heavy metals in our salt mixes. __________________ NO TANKS!!!

09/06/2006, 12:27 PM	#5
RichConley Registered Member Join Date: Sep 2004 Location: Bostonian in Chicago going to DC Posts: 9,908	SeattleRob, if you're only going from 38 to 19 through your RO membrane, either 1) Your TDS meter is bad, 2) your RO membrane is bad. RO membranes should show between a 90 and 99% rejection rate. So with TDS of 38 going out, you should get between 0 and 3 depending on your membrane. You should always get 0 out of the DI. In my new apartment, I get 65 tds on the tap. I get about 2-3 coming out of the RO unit, and 0 coming out of the DI. If 19 is going to your DI, you're going to be replacing it every 2-300 gallons, IIRC. __________________ NO TANKS!!!

09/06/2006, 01:08 PM	#6
HowardW Registered Member Join Date: Feb 2006 Location: Aurora, IL Posts: 1,763	The TDS in our tap water here is over 350 and our water also contains chloramines, phosphates, silicates, and all kinds of other nasty stuff. I wouldn't even consider doing water changes or topping off with our tap water. Some parts of the country however have very low TDS readings on their tap water, I heard one guy say his tap water TDS was 19 __________________ Florida live rock addict

09/06/2006, 03:47 PM	#9
Paul B Premium Member Join Date: Jun 2002 Location: Long Island NY Posts: 15,549	I used tap water in my reef for about the first twenty five years with no problem. Then the town put zinc orthophosphate in the water supply to control corrosion in the pipes. I lost most of my very old corals in a matter of hours. I had to buy 100 gallons of distilled water at a supermarket on Sunday night. Now I have a RO/DI Although my tap water is fine, sometimes it changes. Paul __________________ I used to get shocked when I put my hand in my tank. Then the electric eel went dead. Current Tank Info: 100 gal reef set up in 1971

09/06/2006, 12:03 PM	#2
drummereef Team RC Member Join Date: Jul 2006 Location: STL Posts: 14,754	Algae problems aren't neccessarily the only issue with tap water. There are many other metals and other properties of the water that make it not so great for aquariums. When you get to the DI stage it should basically be reading 0 tds. 0 total disolved solids. Pure. You can't go wrong with pure.

09/06/2006, 12:14 PM	#3
seattlerob Registered Member Join Date: Oct 2005 Location: Seattle Posts: 464	While many of those readings look very low, it's my understanding that things like copper, lead, aluminum, etc will build up over time. So, even though you've been using tap water for over a year now, it's possible at some point in the future this 'build up' of metals will lead to trouble. And, it's likely you'll see the results but will be unsure of the cause. The better test would be a TDS reading of your tap water. As drummerreef mentioned, RO/DI will give you very close to 0 tds. I just purchased the COM-100 TDS meter, and here are my results just to give you an idea of what RO/DI can do: my tap water (seattle): 38ppm tds after RO: 19ppm tds after RO/DI: 0.6ppm tds So, the RO water is 2x 'purer' than tap, and the RO/DI is 60+x 'purer'. Also, not sure where you're located, but I believe 38ppm out of the tap is pretty low compared to some parts of the country. hth, rob

09/06/2006, 02:19 PM	#7
outy Moved On Join Date: Oct 2004 Location: auburn CA Posts: 4,021	mine was 18 yesterday kind of stays around 21 i still have a ro/di and would not run without one.

09/06/2006, 04:04 PM	#10
cheeks69 Registered Member Join Date: Oct 2003 Location: Massachusetts Posts: 418	I have used tap water for 5 years with no problems at all. I have never tested it just add a conditioner and I'm done. I realize in most areas of the country the water quality is real bad and an RO is a must but for me tap it is ! Here's a couple of photos:

09/06/2006, 04:04 PM	#11
melev Moved On Join Date: Sep 2002 Location: Ft Worth, Tx Posts: 43,217	The metals aren't flushed out of the system via water changes, and often are trapped in the sandbed of your tank. If your tank is healthy and happy, you may not need to change your system. Where I've lived, it was necessary to get an RO/DI for my tanks.

09/06/2006, 05:19 PM	#12
thor32766 Registered Member Join Date: Dec 2005 Location: Chuluota, FL Posts: 6,072	wow sweet tank, all i use is a carbon block drinking filter on my tanks __________________ "Live your life so no one has to lie about who you were at your funeral" click on my red house to see my tang compound! Current Tank Info: 29 gallon in Wall!

09/06/2006, 06:02 PM	#13
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Before even considering Tap Water I would suggest two things. Obtain a copy of your water utilities water quality report and study it closely. Next make it a point when you ask for the report to tell the person you are a salt water reef keeper and see if they will refer you to either one of their staff who also keeps fish or corals or to a plant supervisor or senior operator. Explain the same to them and listen to their recommendations. Ask how often they change sources or blends of water or change treatment techniques or chemicals. You might be surprised at how often your tap water changes in a weeks or months time. After storm events or seasonal changes water changes dramatically and thats a bad thing for tank stability. I would never ever recommend tap water to a reefkeeper no matter what part ofthe world they are in simply because it does not have the stability that owning your own RO/DI unit has. You know each time you use it what the water quality is. Things that are safe for human consumption and meet all state and federal regulations may not be safe for corals and things like metals do not go away but stay in your system and build up forever until your system crashes and leaves you scratching your head as to why. Carbon does almost nothing for your tap water except adsorb chlorine and volatile organic chemicals and thats only if its a good one and is changed often.

09/06/2006, 06:53 PM	#15
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Yes but ask that expert if they use a RO/DI and I would almost bet they say yes. My tap water TDS exceeds 700 all the time and can reach over 1000 ppm TDS at times. In the West and Southwest thats common and I sure don't want that in my reef system. I would have to agree with your expert though, water is the single largest component of a reef system and is the most important part of it so why not provide stability by using RO/DI. I have operated and supervised many treatment plants and water systems over the years and none has the stabiity day to day that a little inexpensive RO/DI unit has. Your expert may know corals and fish but he is a littl lacking on water quality knowledge if I may say so.

09/06/2006, 07:06 PM	#16
BHF Premium Member Join Date: Jul 2006 Location: Baltimore, MD Posts: 127	::shrug:: I'm sure Bob Fenner has picked up enough here and there to get by. To each their own, but as Cheeks pretty clearly shows, you can do just fine with tap water.

09/06/2006, 07:08 PM	#17
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Bob is a personal friend and I can always disagree with him. It makes for some fun conversation. If you ever get the chance to spend some time with him I encourage you to do so, the guy is hilarious!

09/07/2006, 05:23 AM	#18
deadfish2 Registered Member Join Date: Apr 2006 Posts: 7	I use the tap water filter and stress coat for my water. Everything fine and I got no alage for my snails.

09/07/2006, 09:32 AM	#21
seattlerob Registered Member Join Date: Oct 2005 Location: Seattle Posts: 464	Rich: when you say seated incorrectly, are you talking about the RO membrane? If so, I can check that. Honestly, when the unit arrived, I did not open any of the canisters to check anything. A couple were a bit loose & leaked, but I just hand tightened them until the leaks stopped. I have a DI bypass and I was measuring TDS of the water com ing out of the bypass. In hind sight, I did not let the water run at all before taking the reading. I just filled up a tupperware with about 2 ounces & then took the reading. When I get home, I'll let it run & discard the 1st gallon or two & then take the reading. I'll bet you're right on the money & hope the TDS reading will be much lower. Either way, I'll post back my results & appreciate your comments rob

09/07/2006, 09:51 AM	#22
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Use a very clean drinking water glass that has no dishwasher soap residue or any visible spotting on it for a sample container. Always triple rinse with DI water after each sample and again when you are done with it. Tupperware and other plastics can give bad readings.

09/07/2006, 09:53 AM	#23
seattlerob Registered Member Join Date: Oct 2005 Location: Seattle Posts: 464	AZDesertRat: thanks for the advice! Appreciate it....learn something new everytime I come here Rob

09/07/2006, 09:56 AM	#24
Tobman Premium Member Join Date: Dec 2005 Location: Steamboat Springs, Colorado Posts: 418	IMHO, really good RO/DI units don't cost that much (esp. compared to all else we spend) and are easy to use. It takes a bit longer to obtain the make up water, but you can do it while you sleep. Just get an RO/DI unit and the question is moot. __________________ Go Broncos! Current Tank Info: 65g reef

09/07/2006, 10:06 AM	#25
RevHtree Registered Member. Join Date: Mar 2005 Location: Chattanooga, Tn. Posts: 2,742	My tank has NEVER seen a drop of RO/DI water. It has been running for about 3 years now. My water is not that bad in my area though.