tds
- Thread starter seascape
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yes, should be fine. its now high in any way.
I wouldn't use any water with a TDS > 0. Without even checking my inline meters I can tell when my TDS gets higher than 0. A few weeks ago I noticed a bit more pane film than normal (needed to be cleaned twice a week vs once a week). I checked my RO water and the TDS was 1. I checked the RO water with my hanna photometer and it read 0.04mg/l (4 consecutive tests). I changed my DI resin and the TDS went back to 0, the po4 of the RO water returned to 0, and my algea growth slowed back up again.
TDS meters aren't very precise at low levels nor do they give any indication of just what molecule/ion/element makes up the reading (if it's >0). I would never use RO/DI water with a TDS reading higher than 0! Starting with water which already has a TDS higher than 0 means your starting with something already in your water that is very likely an unwanted element.
Jeremy
TDS meters aren't very precise at low levels nor do they give any indication of just what molecule/ion/element makes up the reading (if it's >0). I would never use RO/DI water with a TDS reading higher than 0! Starting with water which already has a TDS higher than 0 means your starting with something already in your water that is very likely an unwanted element.
Jeremy
DI media should be changed when you very first start to see anything other than 0 TDS. What people do not realize is DI resin starts to release weakly ionized substances even before it is exhausted, and often in very large quantities. Since they are weakly ionized some will not register on a hobbyist grade TDS meter. These include phosphates, silicates and nitrates among others, all of which can be bad.
If is is showing a TDS reading now when it normally does not with fresh resin you could be doing more harm than good, yes its low TDS but it is probably 100% bad stuff being released.
Change resin at a TDS of 1-2 at most.
Inline meters are my last choice of meters, I own two of them and they are not very accurate in part because they are not truly temperature compensated, they read air temperature not water temperature and how often are they exactly the same? The most accurate handheld hobbyist grade TDS meter is the HM Digital COM-100 which will read 10x lower than any other meter, down in the tenths of a ppm. Much more sensitive and more accurate than any other and still reasonably priced, less than a nice coral frag.
If is is showing a TDS reading now when it normally does not with fresh resin you could be doing more harm than good, yes its low TDS but it is probably 100% bad stuff being released.
Change resin at a TDS of 1-2 at most.
Inline meters are my last choice of meters, I own two of them and they are not very accurate in part because they are not truly temperature compensated, they read air temperature not water temperature and how often are they exactly the same? The most accurate handheld hobbyist grade TDS meter is the HM Digital COM-100 which will read 10x lower than any other meter, down in the tenths of a ppm. Much more sensitive and more accurate than any other and still reasonably priced, less than a nice coral frag.
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Here is the link to the HM Digital website and COM-100 meters:
COM-100: Waterproof EC / TDS / Temp Combo Meter - HM Digital
It is the only hobbyist grade meter capable of registering in tenths that I am aware of.
Here is their TDS-3 which would be my second choice:
TDS-3 Handheld Meter With Carrying Case - HM Digital
Both are very good meters. You can get either from www.buckeyefieldsupply.com who is a master distributor for HM.
Here is their DM-1 dual inline which I hav two of but would not recommend unless you are only looking for a ballpark reading. In the picture you see one of the probes inserted into a john guest tee, on it is printed the word OUT, just under the O in OUT is a small rectangular opening in the probe and that is where the temp probe resides not down inside the tee where it should be. This is where the accuracy is in question since it is reading air temperature and not water temperature and they are hardly ever the same leading to inaccurate readings.
http://www.tdsmeter.com/products/dm1.html
COM-100: Waterproof EC / TDS / Temp Combo Meter - HM Digital
It is the only hobbyist grade meter capable of registering in tenths that I am aware of.
Here is their TDS-3 which would be my second choice:
TDS-3 Handheld Meter With Carrying Case - HM Digital
Both are very good meters. You can get either from www.buckeyefieldsupply.com who is a master distributor for HM.
Here is their DM-1 dual inline which I hav two of but would not recommend unless you are only looking for a ballpark reading. In the picture you see one of the probes inserted into a john guest tee, on it is printed the word OUT, just under the O in OUT is a small rectangular opening in the probe and that is where the temp probe resides not down inside the tee where it should be. This is where the accuracy is in question since it is reading air temperature and not water temperature and they are hardly ever the same leading to inaccurate readings.
http://www.tdsmeter.com/products/dm1.html
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I use the SpectraPure system which includes a water conductivity monitor. I set it to read "time to change" at 0.67 ppm (it can be set as low as 0.33 ppm). Anything above that and I'm not comfortable, even though my inline meter is still showing zero.
Dave
Dave
