something to consider about TDS-warning!

giants4pc · 07/09/2009, 05:08 AM

I have never owned a TDS meter. However, I have had an RO/DI unit essentially since I started this hobby long ago. Last month, I replaced my filters on the Typhoon III. The membrane is two years old. I finally decided to get a TDS meter out of curiosity. I tested the water coming out of the unit and it tested 2. Considering that my membrane is two years old, I thought this was pretty good because I have always read that under 10 is what we want.

I keep a 55 gallon barrel resevoir of RO water. I tested that barrel and it read 280. I thought something was wrong and tested again. Sure enough, 280. I admit that I have never really cleaned this barrel after I started using it a year ago. It's white but it had those stained brown water marks in it. I couldn't believe what it looked like after a heavy duty scrubbing with the hose and some distilled white vinegar. I let it dry and made water overnight and this morning, it tested 17. I need to give it one more solid cleaning, but this was eye opening. Anyone keeping a resevoir, should really clean it. I thought I was using pure water in my reef; needless to say, 280 isn't exactly pure.

cham · 07/09/2009, 06:07 AM

Fresh RO/DI water is devoid of anything and is aggresive in seeking solids to absorb. A good reason to keep a lid on it.

thorsky · 07/09/2009, 09:27 AM

For what it's worth, I've had the same 35g brute sitting in my basement for 2 years. I run my RO/DI when the water gets to 10g or so. My TDS post RO is 0 (70TDS in

) and post maxcap DI is of course still 0. The TDS of my barrell is also 0 and has never changed. I check it monthly. Mine is always covered. Not sure why yours would get so dirty, but something doesn't seem right.

Lance M. · 07/09/2009, 09:46 AM

thorsky-

Do you keep it sealed, like airtight?

thorsky · 07/09/2009, 09:53 AM

Not really. Just the standard brute lid, and I even have a power wire sandwiched in there for my top-off pump.

1DeR9_3Hy · 07/09/2009, 10:08 AM

^^^ I have basicly the same setup, 40 gallon brute with lid and hole in the side of the lid for a pump wire. I measured mine after 4 months of use and my reserve water was around 60 tds. I cleaned it out, and let it dry...it got down to around 7 tds, with 0 tds coming out of the filter. I need to clean it one more time, then i should be down to 0 in the reserve.

I did not have the brown residue, but i did have some slimy feeling stuff on the sides that was near colorless.

giants4pc · 07/09/2009, 09:08 PM

I don't keep a lid on mine because it is a nonstandard/old white plastic barrel. It was a solid piece that I saw in order to make it an open top. I could be more careful and get a cover for it, but it is so much more convenient to leave it open top. Since mine is always up and down, the water just leaves that slimy film. I think that is what contributes to the high reading.

07/09/2009, 05:08 AM	#1
giants4pc Registered Member Join Date: Oct 2004 Location: connecticut Posts: 1,699	something to consider about TDS-warning! I have never owned a TDS meter. However, I have had an RO/DI unit essentially since I started this hobby long ago. Last month, I replaced my filters on the Typhoon III. The membrane is two years old. I finally decided to get a TDS meter out of curiosity. I tested the water coming out of the unit and it tested 2. Considering that my membrane is two years old, I thought this was pretty good because I have always read that under 10 is what we want. I keep a 55 gallon barrel resevoir of RO water. I tested that barrel and it read 280. I thought something was wrong and tested again. Sure enough, 280. I admit that I have never really cleaned this barrel after I started using it a year ago. It's white but it had those stained brown water marks in it. I couldn't believe what it looked like after a heavy duty scrubbing with the hose and some distilled white vinegar. I let it dry and made water overnight and this morning, it tested 17. I need to give it one more solid cleaning, but this was eye opening. Anyone keeping a resevoir, should really clean it. I thought I was using pure water in my reef; needless to say, 280 isn't exactly pure.

07/09/2009, 10:08 AM	#6
1DeR9_3Hy Registered Member Join Date: Dec 2007 Posts: 2,575	^^^ I have basicly the same setup, 40 gallon brute with lid and hole in the side of the lid for a pump wire. I measured mine after 4 months of use and my reserve water was around 60 tds. I cleaned it out, and let it dry...it got down to around 7 tds, with 0 tds coming out of the filter. I need to clean it one more time, then i should be down to 0 in the reserve. I did not have the brown residue, but i did have some slimy feeling stuff on the sides that was near colorless. __________________ I hope it never catches on, I like having the oldest tank on here and I don't have to worry about calcification, bio pellets, Vodka dosing, DSBs, Chaetomorpha (I don't even know what that is) Carbonite hardness and all of these other things many people worry about. If I had to think about all of that stuff I would get a stroke. My test kit came in a wooden box and the directions say to keep in a cool chariott. I throw some food in the tank, wave hello to the fish and go out with my wife and have a nice glass of merlot with dinner. Have a great day but most of all, have fun. -PaulB Current Tank Info: 27 Gallon DAS softy/fish reef

07/09/2009, 06:07 AM	#2
cham Registered Member Join Date: Jun 2006 Location: Winter Garden, FL Posts: 3,632	Fresh RO/DI water is devoid of anything and is aggresive in seeking solids to absorb. A good reason to keep a lid on it.

07/09/2009, 09:27 AM	#3
thorsky Registered Member Join Date: Nov 2003 Location: Rhode Island Posts: 407	For what it's worth, I've had the same 35g brute sitting in my basement for 2 years. I run my RO/DI when the water gets to 10g or so. My TDS post RO is 0 (70TDS in ) and post maxcap DI is of course still 0. The TDS of my barrell is also 0 and has never changed. I check it monthly. Mine is always covered. Not sure why yours would get so dirty, but something doesn't seem right.

07/09/2009, 09:46 AM	#4
Lance M. Registered Member Join Date: Oct 2007 Location: Charleston, SC Posts: 910	thorsky- Do you keep it sealed, like airtight?

07/09/2009, 09:53 AM	#5
thorsky Registered Member Join Date: Nov 2003 Location: Rhode Island Posts: 407	Not really. Just the standard brute lid, and I even have a power wire sandwiched in there for my top-off pump.

07/09/2009, 09:08 PM	#7
giants4pc Registered Member Join Date: Oct 2004 Location: connecticut Posts: 1,699	I don't keep a lid on mine because it is a nonstandard/old white plastic barrel. It was a solid piece that I saw in order to make it an open top. I could be more careful and get a cover for it, but it is so much more convenient to leave it open top. Since mine is always up and down, the water just leaves that slimy film. I think that is what contributes to the high reading.