TDS?

[abaigael04]

I have seen some posts about TDS. Can someone explain this a little better to me? How do you test ?

[tariesindanrie]

TDS refers to the quantity of "stuff" dissolved in the water, whether magnesium, calcium, sodium, or anything else. This is important because it controls how fast water moves into the fish. Pure water would pass through the fish's skin very quickly, which water with a lot of other stuff dissolved in it would move more slowly.

Fish need to use their kidneys to pump this water out. Some fish, like platys, are used to environments where their kidneys don't have to work that hard. Others, like clown loaches, are used to an environment where they rapidly take in water that they use to clean out toxins from their body.

The effect of having the wrong TDS level is usually slow to appear, but it generally reduces the fish's lifespan. Clowns will actually become dehydrated, and potentially have kidney problems. To make a long story short, you need to keep a clown tank water as clean as possible- 20 percent water changes twice weekly are recommended. Hope this helped!


Kate

[abaigael04]

yes that helped a lot - to make sure TDS is at acceptable levels - how do you test/know. Nitrates? my SW friend told me how to test for TDS is very expensive, so how would you know? THANK YOU!

[starsplitter7]

You can buy a TDS (Total Dissolved Solids meter) for $20 online. You just stick it in and the reading pops up. It is that easy.

I keep a record of all my tests on my tanks. When the TDS goes up, you know there's more junk in the water.

[tariesindanrie]

For me, frequent water changes and keeping an eye on the nitrates, pH and kH works fine. Generally speaking, if the pH is too alkaline and the nitrates are spiking, there's too much 'stuff' in the water. Best remedy in this case is a 40% water change- there's lots of chemical 'balancers' and additives on the market to alter pH, but all that adding those really does is change the 'stuff'.

And again, the best prevention is keeping your water and substrate clean. I think you mentioned a large Pleco in a previous post? I have one in my clown tank also, and since I love him even though he is literally a poo machine, I vacuum the gravel and do 20% changes at least twice, and sometimes 3 times weekly.


Kate

[abaigael04]

I do have a pleco, he is not large - yet! I do stay on top of water changes and rarely have nitrates over 10, usually around 5. My ph is 7.6 - from my tap and even if I WANTED to add stuff (which I don't) it doesn't seem to change my pH AT ALL - just makes it unstable. All of my fish have adapted very well, though this is a reason I only buy locally - because they have acclimated the fish to my utterly ridiculous city water (that has ammonia in it, too!). I don't have a kH test, though. I keep a log of all my test results, though and like to make sure I stay constant.... so I will obviously continue to monitor and do my water changes.

[chefkeith]

TDS meters measure the conductivity of the water on a ppm scale. In freshwater aquatics, if you know the initial TDS of the aquarium water (tap water going in), then compare that reading to the current TDS of the aquarium water, the difference between the two numbers will give you a good idea of how much the initial water has changed.

The aquariums TDS will raise for these reasons-

1) Evaporation. (to avoid TDS evaporation increases you could top-off the aquarium with RO water, but evaporation should not turn into a serious issue if you do at least 25% weekly water changes and keep the aquarium covered).

2) Leaching. Something in the tank is leaching in the water ( rocks, gravel, sand, driftwood/peat, almond leaves, dead plants, ect). This isn't necessarily a bad thing. For instance, driftwood or peat can help soften hard water though ion exchange, but it will increase the TDS a little.

3) Contamination or Pollution. Something was added to the water for whatever reason. (fish food/ fish waste, medications, dead plants/algae, decaying organics, or basically anything with charged ions). When fish food/fish waste dissolve, they will add some charged ions to the water and that will raise the TDS.

4) Water Treatments or Modifications. If the source water needs to be modified it should be done consistently before adding the new water to the aquarium. Any regular water modifications should be written down on paper or tracked on a spreadsheet program so that you know the water profiles from the source and from the aquarium. FYI, Water Dechlorinators, kH/gH mixes, and plant fertilizers will add to the TDS.

Another important use for TDS meters is for determining an acclimation procedure for fish that need to be moved to a new environment. If you get some new fish from an LFS or an Importer, the easiest way to determine if the bag water has been salted is with a TDS meter. It is common practice to only measure the pH of the bag water, but pH tests don't detect salt or magnesium. Moving fish from high TDS to low TDS water is the most devastating thing that can happen to fish.

Acclimation isn't just needed for new fish either, fish can have acclimation problems during any water change if the source water's TDS doesn't come close to matching the aquarium water. It would be good practice to monitor the tap water and aquarium TDS to avoid potential water change problems . You never know when the water company will switch water treatment wells, which could result in the TDS being completely different from one week to the next. Mystery fish deaths will probably be more rare if you monitor TDS regularly.


So why does TDS matter to fish? Because it should give you instant feedback if something is different from this water profile from that water profile. If something is different, then you might need to break out the other test kits, such as kH, gH, nitrates, salinity, phosphates, ect, so that you can figure out what the problem is.

[Batch]

You can buy a TDS (Total Dissolved Solids meter) for $20 online. You just stick it in and the reading pops up. It is that easy.

I keep a record of all my tests on my tanks. When the TDS goes up, you know there's more junk in the water.

Really? I was always under the (mistaken) impression that they were expensive. Cool. Can you give us a link to one?

Thanks,
Batch

[abaigael04]

thank you everyone! I understand it MUCH better now! I think I think I will pick up some more tests soon!

[abaigael04]

I searched for them on google and found one for $19.... not sure if there is a good brand or anything, though.

[chefkeith]

A good brand is Hanna. A good range to have is 0 - 9,990. Some only have a range of up to 990 or 1,990.

[Batch]

Hi,
What do you guys think of this one?
HM Digital TDS-EZ Pocket TDS Meter, TDSEZ

One 20ml pack 1382ppm TDS/KCl Solution included for Aquarium/Hydroponics recalibration needs (not included for the order of 10 or more).

FEATURES

1. Economy model that is ideal for end-users. 2. Highly efficient and accurate due to its advanced microprocessor technology. 3. Hold Function: saves measurements for convenient reading and recording. 4. Auto-off function: the meter shuts off automatically after 10 minutes of non-use to conserve batteries. 5. Measurement Range: 0-9990 ppm. From 0-999 ppm, the resolution is in increments of 1ppm. From 1000 to 9990 ppm, the resolution is in increments of 10ppm, indicated by a blinking 'x10' image. 6. Display: large and easy-to-read LCD screen. 7. Factory Calibrated: our meters are calibrated with a 342 ppm NaCl solution. Meters can be recalibrated with a mini-screwdriver. 8. Fun, translucent blue housing that's very strong and durable. 9. Includes a TDS chart sticker on the back of the meter that explains TDS values.

SPECIFICATIONS

1. TDS Range: 0 - 9990 ppm (mg/L) 2. Resolution: 1 ppm (0-999 ppm); 10 ppm (1000-9990 ppm) 3. Accuracy: +/- 3% 4. Power source: 2 x 1.5V button cell batteries (included) 5. Battery life: Approx. 1000 hours of usage 6. Dimensions: 15.5 x 3.1 x 2.3cm (6.1 x 1.25 x 1 inches) 7. Meter weight: 56.7g (2 oz) 8. Weight with package: 76.5g (2.7 oz)

http://www.eseasongear.com/hmditdme.html

Batch

[chefkeith]

That one looks ok, but it only has an accuracy of +/- 3%.

The better ones are +/-2% and have automatic temperature compensation.

[Diana]

That sounds like the one I have, and it works fine. I mainly use it for checking the bag water of new fish so I can adjust the Q-tank water, but I also check my recipes occasionally to be sure I am making Lake Tanganyikan water consistently, and similar uses.

[ulthipster]

Hi everyone,
Thought I'd jump into the conversation as I've always wanted to get a TDS meter as well. I'm put off by my ignorance of what I will need to do to properly calibrate it. Do you have to do this each time you finish or start to use one of the Hanna TDS meters? Which calibration "stuff" should you get....?
Thanks all!

-Tracey