Tap water quality, is it really that bad? - Page 2

AZDesertRat · 09/07/2006, 10:49 AM

Very nice tank! You are fortunate with your water as that is definitely not the norm.

CapnKick · 09/07/2006, 10:54 AM

Nice tank Rev!

I posted the same question in a previous thread, and some very interesting points were brought about re: TDS. However, I agree that 1) water changes will remove accumulated solids and 2) there are so many other things to worry about.

http://www.reefcentral.com/forums/sh...hreadid=912332

RevHtree · 09/07/2006, 11:02 AM

Thanks for the compliments.

Don't get me wrong here. I should have added that in most cases it is very necessary to use a purifying unit for your tanks water. I am going to get one anyway in the near future myself. Maybe I will have to do less glass scraping.

AZDesertRat · 09/07/2006, 11:04 AM

CapnKick,
Waterchanges do not remove accumulated metals and inorganics. They bind with the sand and rock and are not removed. They are cumulative and just keep getting worse with time. Its best to not add them in the first place by using RO/DI.

CapnKick · 09/07/2006, 11:11 AM

Quote:

Originally posted by AZDesertRat
CapnKick,
Waterchanges do not remove accumulated metals and inorganics. They bind with the sand and rock and are not removed. They are cumulative and just keep getting worse with time. Its best to not add them in the first place by using RO/DI.

Please excuse my ignorance on this point. Do TDS include both organics and inorganics? Are we talking about everything in water other than H2O, or just the undissolved solids? Or does this include dissolved solids? I guess I'm confused as to what TDS are and how they affect our systems.

CapnKick · 09/07/2006, 11:14 AM

And now that I read what I just wrote I realize how stupid that question is...clearly we're talking about total DISSOLVED solids. However, if anyone more fluent in chemistry can please explain the effects on marine systems it would be much appreciated. Also, are we talking about organic or inorganic?

AZDesertRat · 09/07/2006, 11:46 AM

TDS can be both. Its really a poor measure of water quality as some constituents are not ionized either positively or negatively enough to read well with a TDS meter. Short of chemical analysis its the best we hvae for the hobby though.
Metals like copper which are present in most tap water up to a legal Maximum Contaminant Level of 1.3 mg/L are detrimental to a reef system. Remember EPA standards are set for human consumption not for saltwater reefs. Phosphates can be added to tap water for corrosion control and are another bad thing in a reef. Phosphates are very weakly ionized and even though they can be captured by DI resin they are also one of the first things it releases when it starts to reach exhaustion. Silicates are similar to phosphates. There are any number of things like this that are allowable in any and all municipal water systems in the US but are not good for your tank and its inhabitants.

CapnKick · 09/07/2006, 12:07 PM

So I conjecture that the assumed behavior of these solids is that they eventually fall out of solution and bind with the substrate, rocks, tank and anything else they can bind to. Also, to the extent they remain dissolved, any buildup could be foreboding for algae control, diatom control, dinoflagellates, etc.

Assuming water changes can remove (and replenish without RO/DI, to some extent) the DISSOLVED solids, is there a risk from those that have binded to the interior components of the tank? Can they be leaching chemicals into the water column?

AZDesertRat · 09/07/2006, 12:17 PM

We probably need to move this over to the Reef Chemistry forum and have Randy address this.

Nathan · 09/07/2006, 12:26 PM

I have always had horrible quality water, so RO/DI is absolutely necessary for me. My city water is artesian well water.

Phosphates are so high the test turned inky blue.
Nitrates are high as well.
Lots of grit in the water as can be seen in my micron filter.

I will only ever use RO/DI water as long as I live with this city water.

CapnKick · 09/07/2006, 12:34 PM

Quote:

Originally posted by AZDesertRat
We probably need to move this over to the Reef Chemistry forum and have Randy address this.

Good call - I'm curious what Randy's standpoint would be on what happens to the TDS once in the system, how the buildup affects the system, etc. Do you know how to move the thread?

Randy Holmes-Farley · 09/07/2006, 02:57 PM

Please excuse my ignorance on this point. Do TDS include both organics and inorganics? Are we talking about everything in water other than H2O, or just the undissolved solids? Or does this include dissolved solids? I guess I'm confused as to what TDS are and how they affect our systems.

A conductivity meter (reporting in TDS or other units) includes anything in the water that is charged, but in tap water that will almost entirely be comprised of inorganics, and most of the will be simple ions like sodium, chloride, calcium, etc. None of these are a concern for reef aquaria.

Some metals, like copper, and some anions (like phosphate) can also be a concern, and are why I do not recommend using tap water.

Copper and other metals will bind to organics and inorganics (like calcium carbonate) in a reef aquarium. Enough can stay in solution to be toxic in some cases.

These articles may be useful:

Tap Water in Reef Aquaria
http://www.advancedaquarist.com/issues/jan2004/chem.htm

What is TDS?
http://www.reefkeeping.com/issues/20...ture/index.php

AZDesertRat · 09/07/2006, 03:28 PM

Thanks Randy!!!

CapnKick · 09/07/2006, 03:30 PM

Yes, thanks Randy - that really clears up my curiosity.

seattlerob · 09/07/2006, 05:28 PM

Rich & AZDesertRat: since curious minds have to know, I did retest my all my water for TDS. This time, I let the water run for a bit before I took the sample, and also used a clean glass instead of tupperware. These readings are from a HM COM-100 TDS meter:

tap: 35ppm
RO: 1.8ppm
RO/DI: 0.4-0.5ppm

Those numbers seem more inline with a good working RO/DI unit I guess!

Interestingly, when I sample RO/DI that's been sitting in a 10g rubbermaid container (white trash can), the TDS reading right now is 1.3ppm. So, AZ's note about plastics giving bad readings seems to hold true. I am guessing the really pure RO/DI is absorbing TDS from the container and/or air. Makes me wonder if I should be using a different container to store the water in, such as glass, and whether I should cover the container as well (currently I just leave it open, but it is inside a cabinet)...

AZDesertRat · 09/07/2006, 06:35 PM

Much better numbers! I would cover or somehow seal the storage container though. I love my COM-100, nothing even comes close to its accuracy or sensitivity on the low end. Its nice to be able to test water down to about 10 megaOhms resistivity which is absolutely great water.

seattlerob · 09/07/2006, 09:44 PM

AZ: truth be told, the fact I own a COM-100 is due your high recommendation I've read in several posts about RO/DI & TDS

As is so true with this hobby, I try to research as much as I can & hopefully make good choices along the way!

I'm sure I can find something to cover the water with. I remember thinking when I bought it that I wish it had a cover...oh well.

Rob

Quote:

Originally posted by AZDesertRat
Much better numbers! I would cover or somehow seal the storage container though. I love my COM-100, nothing even comes close to its accuracy or sensitivity on the low end. Its nice to be able to test water down to about 10 megaOhms resistivity which is absolutely great water.

The_Alchemist · 09/08/2006, 12:31 AM

Thank you to everyone for your replies... i'm learning alot and have attempted to call the water quality manager in our area but can't seem to get through..

I want to obtain a detailed report of the TDS and general water quality value's for this region and any possible fluctuations, and will make a judgement then as to whether i should invest in RO/DI..

For the mean time, thanks again.

The Alchemist.

CapnKick · 09/08/2006, 08:42 AM

Mine are available online...where'd that link go...look in my post that I linked to above, I think it's the utility's website.

CapnKick · 09/08/2006, 08:43 AM

sfwater.org

09/07/2006, 10:54 AM	#27
CapnKick Registered Member Join Date: May 2006 Location: San Francisco Posts: 189	Nice tank Rev! I posted the same question in a previous thread, and some very interesting points were brought about re: TDS. However, I agree that 1) water changes will remove accumulated solids and 2) there are so many other things to worry about. http://www.reefcentral.com/forums/sh...hreadid=912332 __________________ Curator of the North Point Marine Aquarium & Bar Current Tank Info: 120G reef, 29G sump/refugium, 2x250W DE MH, 4x110W VHO, AquaC EV180

09/07/2006, 11:14 AM	#31
CapnKick Registered Member Join Date: May 2006 Location: San Francisco Posts: 189	And now that I read what I just wrote I realize how stupid that question is...clearly we're talking about total DISSOLVED solids. However, if anyone more fluent in chemistry can please explain the effects on marine systems it would be much appreciated. Also, are we talking about organic or inorganic? __________________ Curator of the North Point Marine Aquarium & Bar Current Tank Info: 120G reef, 29G sump/refugium, 2x250W DE MH, 4x110W VHO, AquaC EV180

09/07/2006, 12:07 PM	#33
CapnKick Registered Member Join Date: May 2006 Location: San Francisco Posts: 189	So I conjecture that the assumed behavior of these solids is that they eventually fall out of solution and bind with the substrate, rocks, tank and anything else they can bind to. Also, to the extent they remain dissolved, any buildup could be foreboding for algae control, diatom control, dinoflagellates, etc. Assuming water changes can remove (and replenish without RO/DI, to some extent) the DISSOLVED solids, is there a risk from those that have binded to the interior components of the tank? Can they be leaching chemicals into the water column? __________________ Curator of the North Point Marine Aquarium & Bar Current Tank Info: 120G reef, 29G sump/refugium, 2x250W DE MH, 4x110W VHO, AquaC EV180

09/07/2006, 02:57 PM	#37
Randy Holmes-Farley Reef Chemist Join Date: Apr 2001 Location: Arlington, Massachusetts Posts: 86,233	Please excuse my ignorance on this point. Do TDS include both organics and inorganics? Are we talking about everything in water other than H2O, or just the undissolved solids? Or does this include dissolved solids? I guess I'm confused as to what TDS are and how they affect our systems. A conductivity meter (reporting in TDS or other units) includes anything in the water that is charged, but in tap water that will almost entirely be comprised of inorganics, and most of the will be simple ions like sodium, chloride, calcium, etc. None of these are a concern for reef aquaria. Some metals, like copper, and some anions (like phosphate) can also be a concern, and are why I do not recommend using tap water. Copper and other metals will bind to organics and inorganics (like calcium carbonate) in a reef aquarium. Enough can stay in solution to be toxic in some cases. These articles may be useful: Tap Water in Reef Aquaria http://www.advancedaquarist.com/issues/jan2004/chem.htm What is TDS? http://www.reefkeeping.com/issues/20...ture/index.php __________________ Randy Holmes-Farley Current Tank Info: 120 mixed reef

09/07/2006, 03:30 PM	#39
CapnKick Registered Member Join Date: May 2006 Location: San Francisco Posts: 189	Yes, thanks Randy - that really clears up my curiosity. __________________ Curator of the North Point Marine Aquarium & Bar Current Tank Info: 120G reef, 29G sump/refugium, 2x250W DE MH, 4x110W VHO, AquaC EV180

09/07/2006, 10:49 AM	#26
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Very nice tank! You are fortunate with your water as that is definitely not the norm.

09/07/2006, 11:02 AM	#28
RevHtree Registered Member. Join Date: Mar 2005 Location: Chattanooga, Tn. Posts: 2,742	Thanks for the compliments. Don't get me wrong here. I should have added that in most cases it is very necessary to use a purifying unit for your tanks water. I am going to get one anyway in the near future myself. Maybe I will have to do less glass scraping.

09/07/2006, 11:04 AM	#29
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	CapnKick, Waterchanges do not remove accumulated metals and inorganics. They bind with the sand and rock and are not removed. They are cumulative and just keep getting worse with time. Its best to not add them in the first place by using RO/DI.

09/07/2006, 11:46 AM	#32
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	TDS can be both. Its really a poor measure of water quality as some constituents are not ionized either positively or negatively enough to read well with a TDS meter. Short of chemical analysis its the best we hvae for the hobby though. Metals like copper which are present in most tap water up to a legal Maximum Contaminant Level of 1.3 mg/L are detrimental to a reef system. Remember EPA standards are set for human consumption not for saltwater reefs. Phosphates can be added to tap water for corrosion control and are another bad thing in a reef. Phosphates are very weakly ionized and even though they can be captured by DI resin they are also one of the first things it releases when it starts to reach exhaustion. Silicates are similar to phosphates. There are any number of things like this that are allowable in any and all municipal water systems in the US but are not good for your tank and its inhabitants.

09/07/2006, 12:17 PM	#34
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	We probably need to move this over to the Reef Chemistry forum and have Randy address this.

09/07/2006, 12:26 PM	#35
Nathan Premium Member Join Date: Mar 2000 Location: Newtown, Pa., USA Posts: 1,454	I have always had horrible quality water, so RO/DI is absolutely necessary for me. My city water is artesian well water. Phosphates are so high the test turned inky blue. Nitrates are high as well. Lots of grit in the water as can be seen in my micron filter. I will only ever use RO/DI water as long as I live with this city water.

09/07/2006, 03:28 PM	#38
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Thanks Randy!!!

09/07/2006, 05:28 PM	#40
seattlerob Registered Member Join Date: Oct 2005 Location: Seattle Posts: 464	Rich & AZDesertRat: since curious minds have to know, I did retest my all my water for TDS. This time, I let the water run for a bit before I took the sample, and also used a clean glass instead of tupperware. These readings are from a HM COM-100 TDS meter: tap: 35ppm RO: 1.8ppm RO/DI: 0.4-0.5ppm Those numbers seem more inline with a good working RO/DI unit I guess! Interestingly, when I sample RO/DI that's been sitting in a 10g rubbermaid container (white trash can), the TDS reading right now is 1.3ppm. So, AZ's note about plastics giving bad readings seems to hold true. I am guessing the really pure RO/DI is absorbing TDS from the container and/or air. Makes me wonder if I should be using a different container to store the water in, such as glass, and whether I should cover the container as well (currently I just leave it open, but it is inside a cabinet)...

09/07/2006, 06:35 PM	#41
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Much better numbers! I would cover or somehow seal the storage container though. I love my COM-100, nothing even comes close to its accuracy or sensitivity on the low end. Its nice to be able to test water down to about 10 megaOhms resistivity which is absolutely great water.

09/08/2006, 12:31 AM	#43
The_Alchemist Registered Member Join Date: Aug 2006 Posts: 11	Thank you to everyone for your replies... i'm learning alot and have attempted to call the water quality manager in our area but can't seem to get through.. I want to obtain a detailed report of the TDS and general water quality value's for this region and any possible fluctuations, and will make a judgement then as to whether i should invest in RO/DI.. For the mean time, thanks again. The Alchemist.

09/08/2006, 08:42 AM	#44
CapnKick Registered Member Join Date: May 2006 Location: San Francisco Posts: 189	Mine are available online...where'd that link go...look in my post that I linked to above, I think it's the utility's website. __________________ Curator of the North Point Marine Aquarium & Bar Current Tank Info: 120G reef, 29G sump/refugium, 2x250W DE MH, 4x110W VHO, AquaC EV180

09/08/2006, 08:43 AM	#45
CapnKick Registered Member Join Date: May 2006 Location: San Francisco Posts: 189	sfwater.org __________________ Curator of the North Point Marine Aquarium & Bar Current Tank Info: 120G reef, 29G sump/refugium, 2x250W DE MH, 4x110W VHO, AquaC EV180