A couple of things

Gringos · #1 06-15-2005, 03:10 AM

I got myself a TDS meter for my ro unit. When will I know when to change my membrane. Readings 35 going in and 0 going out.

I opened up a new bucket of instant ocean salt mix and mixed my first batch of salt with it. So I did a couple of tests. Alk 10.9dkh, PH 8.2, Ca 380ppm. Is it normal that the ALK is so high? Should I test for anything else before using the salt. I keep reading about bad salt, how would I know if mine is bad. Plus there is a bit of caking in the bottom.

On to the good stuf. I just got myself a new fish. Just what I wanted, went back to LFS and there was the copperbanded I had seen this weekend. Still looked good and eats mysis. So I got him in my qt and put a bit of rock with feather dusters on it. Safe to say he ate them all, so I gave him some shrimp and he ate them too. I had to put him in a 10g for now, having problems with my 30g. But if all goes well I think I will put him in my display in a week. Because he looks cramped in there, barely moves during the day. But when the lights go out, hes all over the place. I read they were more active at night but this is not what I expected. Can I expect a more active fish in my 125g? Would he benefit from moon lights?

Aquattro · #2 06-15-2005, 03:58 AM

When TDS starts to go above 0, time to change membrane. Those readings with RO and IO salt are perfectly normal. The "bad" salt had alk inthe 30's, IIRC. It mixed milky white and stayed that way.

StirCrazy · #3 06-15-2005, 12:39 PM

just to clarify I would not change the membrane if the reading increased to 1 ppm, but if it got over 3 or 4 then ya.

Steve

Johnny Reefer · #4 06-15-2005, 02:50 PM

Quote:

Originally Posted by Gringos

Readings 35 going in and 0 going out.

It is my understanding, from reading subject material, that RO removes many things. Phosphate, nitrate, copper, lead, aluminum, mud, organic matter, chlorine and chloramine. The author of the material I read did not go into readings.
What substance is being read by the TDS meter?
Also, TDS? What does that stand for?

Thanx much,

SuperFudge · #5 06-15-2005, 03:22 PM

TDS= Total Dissolved Solids

FWIW, You can have 10 or 20 ppm TDS, and your water still be perfectly fine for use in your tank...or it can be reading 5 ppm and be absolutley usless for your tank. (its more what substance the 5ppm actually is)

For that reason, TDS is not really a good measure for overall water quality.

Its more the "increase" of them being noticed with your meter, in telling you when its time to change the membrane.

Kinda funny actually, the Kent TDS meter doesnt even register until 50 PPM.

Marc.