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Do I need to test for water hardness?

3301 Views 25 Replies 5 Participants Last post by  detroit_fan
I have the API master kit, but do I need to test for water hardness too? I have a TDS meter, will that tell me anything about the hardness?

Update- TDS reading 130
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Unless you expect your water to be very hard, it is not really neccesary. About the TDS meter, TDS measures everything. It is impossible to have less than 100 TDS with hard water, but the other way around is not true; it is possible to have 0 hardness and still a high TDS (from other salts in the water) so it doesn't say much. TDS is more helpful to monitor over time to see whether it gets higher. Also when you know your hardness, TDS can give you a little information about whether there are a lot of other minerals/salts in your water.
TDS measures all the stuff in the water (especially charged particles, but that is almost everything) It is not a specific measure for harness (either General Harness or Carbonate Hardness). As a very rough guide TDS under 200 ppm is pretty soft, 200-800 is middle range to somewhat hard, and over 800 is quite hard. If your TDS says under 200 or over 800 I would want to dig into the exact values for GH and KH.

If you can get a water quality report from your water company that might have all the info you need. General hardness may also be called total hardness, and carbonate hardness may also be called alkalinity. Either may be measured any of several ways, one way is to report the value as ppm-CaCO3 meaning parts per million as if it was all from calcium carbonate (it usually is, but not always)
The other thing to look for in your water quality report is separate tests for calcium (Ca) and magnesium (Mg). These are highly likely in ppm.

You can go to the nearest fish store (not pet store) and ask if they are on the same water system as you. If they treat the water at all. What the test results are for that water.

You can take a sample of your water to a store that tests it for you. Some have a small charge. Get the actual numbers, the test results, not just a comment like 'It is OK'.

An informal water hardness test: Do you have white or off-white crusty stuff around sinks? If yes, these are almost always the minerals that indicate hard water.
Another informal test: Does soap lather well? Or not? Soap does not lather well in hard water.
Another informal test: Do all your neighbors have water softeners? It is probably because of hard water, though 'keeping up with the Jones' factor may play a part.
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Now... do you need to do any of this?

You might not need to. I would look at the water quality report and go from there. If any of the informal tests I suggested say you have extremely hard water or extremely soft water you might want to look into it more carefully.

Most aquarium plants are quite adaptable to a wide range of water harness. There are only a few that really require soft, acidic water.
Most fish that have been hatchery raised are tolerant of a wide range of water hardness. There are many fish, however that still require either very soft or very hard water. If you know what your water is like then you can select fish that are best suited to that water.

If you decide you want to keep fish that are not suited to your water then you will need GH and KH tests to help you set up and maintain water for those fish.
If you are willing to work with the fish that are suited to your water then all you need to do is find out what that water is once. While water company water can change over the year, depending on the source, it usually does not change that much. You can ask the water company about that, too.
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Thank you very much for the helpful replies. I just did a TDS test on my water and I have a TDS of 130. I also found my latest water report online, here is a link to it-

http://www.egovlink.com/public_docu...tilities/2011 Annual Water Quality Report.PDF

I do not have any good LFS in town, only a petsmart. I normally do not go to petsmart as i prefer independently owned LFS's, but does petsmart test water for free?

Do you think with a TDS that low I need to do more testing?
I noticed you are in Monroe, MI. I am right down the road from you in Toledo. There is a pretty decent LFS here, Trilby Tropicals, that carries a decent line of aquarium plants and a nice selection of tropical fish. Might want to stop in there if you are ever down this way.
I noticed you are in Monroe, MI. I am right down the road from you in Toledo. There is a pretty decent LFS here, Trilby Tropicals, that carries a decent line of aquarium plants and a nice selection of tropical fish. Might want to stop in there if you are ever down this way.
Hi neighbor, I actually was at Trilby last week, purchased a nice piece of driftwood from them. They were just starting to get plants in, said they don't get many in the summer due to them not shipping well in the heat, so I am looking forward to going back there in a month or 2 when they are fully stocked up on them.

By chance are you a member of the TRAC forum?
Well, the water quality report did not cover any of the things that we test for with GH and KH tests.

Just going by the TDS test your water seems to have a low level of stuff in it, so without GH and KH tests I would suggest you are fine to keep most soft water fish, but would need to add some minerals if you want hard water fish (mostly live bearers, some rainbows and a long list of Cichlids, mostly from the Rift Lakes).

The Pet Smart near me does test water, but make sure you get the actual numbers.
Well, the water quality report did not cover any of the things that we test for with GH and KH tests.

Just going by the TDS test your water seems to have a low level of stuff in it, so without GH and KH tests I would suggest you are fine to keep most soft water fish, but would need to add some minerals if you want hard water fish (mostly live bearers, some rainbows and a long list of Cichlids, mostly from the Rift Lakes).

The Pet Smart near me does test water, but make sure you get the actual numbers.
Ok, I'll try and get it tested and report back with some numbers. Thank you for your help.
Well i'm an idiot. I had an API KH test kit here the whole time down in my fishroom. The reading appears to be about 4dKH
There is debate on whether a lack of KH buffers can lead to a pH crash or not.
I have seen pH drop off the testing chart once on a trimmings tank going below 5.6pH and tested KH was zero. I tank with 100% RO that's mineral set to parameters of 3-5dGH and 2dKH both injected and 'low tech'. Plants need a minimum GH value to not be calcium deficient. I feel having known KH buffer values is safer for my critters and I know what final pH levels will be on my tanks.

Measurements are in leveled spoons
To increase KH
1/8 TSP : 6.5gallons = 1dKH
1/4 TSP : 13.2gallons = 1dKH
1/2 TSP : 26.4 gallons = 1dKH
I use Arm & Hammer

There is again even more debate over the sodium content of the BS but in YEARS of using it I've never had a problem and the results are consistent.

HTH
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There is debate on whether a lack of KH buffers can lead to a pH crash or not.
I have seen pH drop off the testing chart once on a trimmings tank going below 5.6pH and tested KH was zero. I tank with 100% RO that's mineral set to parameters of 3-5dGH and 2dKH both injected and 'low tech'. Plants need a minimum GH value to not be calcium deficient. I feel having known KH buffer values is safer for my critters and I know what final pH levels will be on my tanks.

Measurements are in leveled spoons
To increase KH
1/8 TSP : 6.5gallons = 1dKH
1/4 TSP : 13.2gallons = 1dKH
1/2 TSP : 26.4 gallons = 1dKH
I use Arm & Hammer

There is again even more debate over the sodium content of the BS but in YEARS of using it I've never had a problem and the results are consistent.

HTH
Thank you very much for the reply and information. I read the test procedure wrong and thought I was looking for a blue color, but actually I was supposed to wait until yellow. I'm very relieved now because I thought I was at 1KH, but I'm actually at 4KH.

Thanks for breaking down the BS numbers, that will be very helpful.

I will be adding a PH probe this week, so I will be able to constantly see PH values
haha! (cool) with live healthy growing plants don't get to hung up on pH values.
Lightly buffered tanks like mine with 2dKH water change everyday almost a full pH point without harm. During the photo period the plants use up the CO2 and the pH rises.
So when you look in the morning before the lights come on and again in the afternoon after they have been burning for awhile and see a higher value don't freak out.
haha! (cool) with live healthy growing plants don't get to hung up on pH values.
Lightly buffered tanks like mine with 2dKH water change everyday almost a full pH point without harm. During the photo period the plants use up the CO2 and the pH rises.
So when you look in the morning before the lights come on and again in the afternoon after they have been burning for awhile and see a higher value don't freak out.
sounds good, thanks again for you help!:smile:
4 dKH is just fine for pretty much all the soft water fish, and pretty much all plants. It is plenty to keep the pH stable. There will be a pH swing from CO2, and the fish handle this just fine.

Next, the GH. This is the test that will suggest if there is enough calcium and magnesium for the plants. If the value is really low (like 3 degrees or under) then I would suggest testing for calcium.
Plants generally use calcium and magnesium in a ratio of about 3-4 parts calcium to 1 part magnesium. The water does not have to have this ratio, but it must have some of each.
If the GH is higher than 3 degrees then I would go ahead and plant, run the tank, and watch for deficiencies. Most of the time, if the GH is moderate or higher there is enough of each Ca and Mg, even if the ratios are weird, that the fish and plants will do just fine. It is at the low end that I worry that one or the other (usually calcium) might be in short supply.
4 dKH is just fine for pretty much all the soft water fish, and pretty much all plants. It is plenty to keep the pH stable. There will be a pH swing from CO2, and the fish handle this just fine.

Next, the GH. This is the test that will suggest if there is enough calcium and magnesium for the plants. If the value is really low (like 3 degrees or under) then I would suggest testing for calcium.
Plants generally use calcium and magnesium in a ratio of about 3-4 parts calcium to 1 part magnesium. The water does not have to have this ratio, but it must have some of each.
If the GH is higher than 3 degrees then I would go ahead and plant, run the tank, and watch for deficiencies. Most of the time, if the GH is moderate or higher there is enough of each Ca and Mg, even if the ratios are weird, that the fish and plants will do just fine. It is at the low end that I worry that one or the other (usually calcium) might be in short supply.
I don't have a GH test kit here, but since I am coming from saltwater I do have a Salifert calcium test kit, which says it is compatible with SW & FW. Would it be a good idea to test for my Calcium?

I also have a Salifert Magnesium test kit, but unfortunately it is only for SW tanks.
Sounds good! Go for it! I wish I could have found a Ca test that is good for fresh. I guess I did not look far enough.

You might even be able to trick the Mg test. Try adding a lot of salt to the fresh water. Since there is no Mg in salt, but maybe the test reagents need the salt it might read correctly. Who knows!
Ok, did a calcium test on my tapwater. the result was 35ppm
Then I would assume that there is probably also some magnesium there, and go a head with a tank geared toward soft water fish.

If you want hard water fish (live bearers, many Rainbows, many Cichlids) then you will have to raise the GH and KH.
thanks Diana. my current plan for stocking is a school of cardinals and some cory cats. from what i have read it seems both are good choices for this water.
detroit_fan said:
Quote:

Originally Posted by ProndFarms

I noticed you are in Monroe, MI. I am right down the road from you in Toledo. There is a pretty decent LFS here, Trilby Tropicals, that carries a decent line of aquarium plants and a nice selection of tropical fish. Might want to stop in there if you are ever down this way.

Hi neighbor, I actually was at Trilby last week, purchased a nice piece of driftwood from them. They were just starting to get plants in, said they don't get many in the summer due to them not shipping well in the heat, so I am looking forward to going back there in a month or 2 when they are fully stocked up on them.

By chance are you a member of the TRAC forum?
Hi there! I apologize for not seeing this earlier as I check these forums daily. To answer your question though, yes, I am a member on the TRAC forum. Feel free to shoot me a PM if you like. It's always great to meet local people!



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