TDS?

[Curtis]

Probably wouldn't hurt to check it from time to time against a known source like a calibration solution, but you probably don't have any real reason to bother, given that we are not going for extreme precision, in a laboratory I can see the reason to be more concerned.

[ulthipster]

I got my HM TDS-4 last week and finally tried it today. We have well water and untreated the meter reads 352, when using our sodium water softener it reads 336. My tanks ranged from 417, 409, 600 to 470 so far what tanks I've tested anyway. The 600 one is an overcrowded angel fry tank with parents and awaiting a move! I have 150 babies I have to split up asap to properly grow out! All my fish are thriving and eating well.

[plaalye]

After reading this thread I purchased an HM TDS-3 meter. I just received it today and tested my tapwater and all my tanks. My numbers dont seem to jive with what's been posted by the rest.
My tap water, after setting overnight and with a few drop of prime measured 49, straight out of the tap was 45. Tanks were 79, 84, 97, 105, and 135. All but the 5 gal. that was 135 were changed today.
I know it's the difference between the tap water and the tanks that we're looking for but my initial reading of 45/49 is so much lower than what seems normal compared to the posts in this thread.
What do you think???

[Diana]

I think you have some incredibly soft water, and that is reflected in the tanks. You are starting with almost nothing in the water, and the traces of fish food, plant fertilizer and so on is adding to what is in the water in the tanks.

Such water would probably be fantastic to breed the rain forest fish that come from such soft water and are hard to breed.

[chefkeith]

plaalye- Like Diana said, that's very possible. Many places on the East Coast have really soft water.
Are you able to keep the kH steady? Are your fish having any kind of problems?

[plaalye]

Thanks for your replies Diana and Chefkieth. I was wondering if maybe the meter wasn't caibrated properly. I've emailed the company I bought it from.
The only test I've done for Kh/Gh is with some outdated Mardel strips I got with a small aquarium that I bought at a yard sale. The readings were Total hardness-about 60: Buffering capacity 80. I don't even know which is which? I'm going to buy a KH/GH test tomorrow.
My Ph is steady at about 7.2 according to the liquid API test I use. All other parameters are fine. These are 10, 20, 20l, &29 gal. tanks and the 2 are pretty heavily stocked so I do have to keep up on the changes to keep the nitrates down.
Everything has been fine with the fish for several months until just last week I lost 2 of my 3 gastromyzons in my rivertank. They rapidly lost weight and died. I've treated the tank with Levamisole and Kanamycin.