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I have been keeping fish for about 6 years nw and have never measured KH. In fact I dont even know what it means (potential hardness or something?) The only parameter I have ever measured is pH but I haven't even measured that in two years. I mean I do regular water changes. I know my water is slightly acidic because the driftwood in there makes the water look acidic or slightly red. I dont often have a fish die for an unknown reason.

So coming back to my first question. Does anyone measure these parameters and is it even neccissary to do so given that you have a larger tank and do regular water canges?

KH stands for carbonate hardness, and I think the K comes from the Germans.

I do not measure hardness, neither KH nor GH. It is not important to the health of most fish species, and is more specific for more difficult breeding purposes, buffering for african cichlids, and shell-building for inverts. None of these are parts of the hobby I enjoy, and so have never had the need to track hardness. On the other hand, if you have trouble lowering your pH because of your water, then testing the KH or GH may be wise to find out if that is the reason for the buffering capacity.

I haven't measured for nitrogenous wastes either. I've never owned a nitrate test kit as nitrate is generally not toxic to freshwater fish. I do have an ammonia test kit but I haven't used it in a while; there's really no reason to expect that it will even be present.

However, there is the flip side to not testing, and that is you may be letting something get out of hand without knowing. This is a potential problem with not testing for a period of time. I'm curious what reading you would get if you tested your pH now, just for kicks. It might actually be lower than you though, and lower than you are comfortable with.

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The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.

I test occasionally for kh as my tap water is very soft and therefore has little buffering capacity. To avoid a pH crash I tend to keep the kh at 2-3 using bicarbonate of soda at water changes.

I should keep it higher for stability, but my fish are all softwater anyway so a low value suits them better and it's not that much work to add a teaspoon now and again.

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I measure KH and GH as I have a comparison chart that links the KH PH to give me a general CO2 level. But that is really all I use it for.

If you haven't tested the PH in a while I would bet that with DW in the tank your PH is 6.0 or even below!

mts.gif" border="0"> I vote do you?
My Tanks at Photobucket

Hey you were right. My pH is around the 5.5 which means its high time I changed the water.
So KH stands for general hardness is GH the same thing or something different?

Hi,
KH is Carbonate Hardness and is a measure of the water's
buffering ability,
GH is General Hardness and is a measure of the Calcium and
Magnesium ions in the water.

If your Carbonate hardness is low, then small things
such as the addition of driftwood to a tank or even
aging of the tank and its water will cause the pH to
make large changes as the water can no longer buffer itself.

The older the tank water is the more acidic it becomes
due to the buildup of organic waste and organic acids.

When injecting CO2 to encourage plant growth, one must
measure the KH and pH of the water and then plot them
on a graph, the point where the two intersect is the
CO2 saturation.

If your water truly has a pH of 5 then DO NOT make any
large changes in the water. You don't want to shift the
pH any more than one or two points in a 24 hour period.
When shifting the pH, the fish have to adjust their
metabolism to compensate for the shift. Too large a shift
will outright kill them, and large shifts tax their
immune systems as well as other body systems.

You should also check your Nitrate reading. I'd be willing
to bet it is "sky high." It gets that way from lack of
water changes and lack of gravel vacuuming. I'd be
willing to bet you have what is called OTS or Old Tank
Syndrome.

Here is something on the OTS:
http://www.bestfish.com/oldtank.html

When vacuuming the gravel, look at your tank and divide
the non-planted parts into 4 sections. With each
weekly water change, vacuum A different section.
That way, over a months time, you will have done
your water changes and vacuumed the entire tank
leaving enough time between vacuuming any one section
for the nitrifying bacteria colonies to have recovered.

If your pH truly is 5, I would change out no more than
10% every other day and once a week do the vacuuming until
everything is back to where it should be.

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

I've been in that situation where my tank pH had crashed (health issues). However I did daily 20% changes for a week with no problems on the test results to get the tank parameters back to being similar to those of the tap water.

Unless you're using a UGF you can vac the entire substrate without any ill effects as the cycle bacteria colonies are in the filter and so won't be disturbed. Of course, if you do have a UGF then you need to take care and only do a section at a time.

Mature, sensible signature required for responsible position. Good prospects for the right candidate. Apply within.

Hi,
Actually, No.
Unless you have a DIY filter that is actually another
tank, the bulk of the nitrifying bacteria colonies
are in the gravel. They cover the surface area of each
individual grain. They are also found on the inside
surfaces of the tank and on any ornaments.

The only difference in vacuuming between the tanks with,
or without a UGF is that without a UGF, you clean right
down to the glass bottom and with a UGF, of course you
clean down to the filter plate.

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

Not sure why the bulk of the bacteria would be in the gravel rather than the filter (internal or external) unless an UGF was being used. Otherwise what is the point to the filter as opposed to a simple powerhead? And where would the bacteria be in my tanks with their sand substrate?

Surely the bacteria are located in the high flow area so they can make use of the ammonia being drawn through?

Mature, sensible signature required for responsible position. Good prospects for the right candidate. Apply within.

As where I live, the water here has a nickname; liquid rock. The ph runs 8.5 out of the tap on average. And the hardnesses are off the chart, or at least to the top level of the charts. Thus, for fish that require these parameters and such, in the tanks I just do water changes and do no other adjustments to the tank, I never check the ph or the hardness.

But, for those tanks that get RO in any amount, they get checked for both ph and hardness weekly. And for any extreme specialty tanks, like the one where I keep the ph at 5.5 currently, and barely any measurement of hardness, gets checked on a daily basis for both ph and hardness.

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There is always a bigger fish...

Not sure why the bulk of the bacteria would be in the gravel rather than the filter (internal or external) unless an UGF was being used. Otherwise what is the point to the filter as opposed to a simple powerhead? And where would the bacteria be in my tanks with their sand substrate?

Surely the bacteria are located in the high flow area so they can make use of the ammonia being drawn through?

Bacteria colonize surfaces, and are therefore everywhere in the tank. However, in areas with higher surface area there are more bacteria, not because they prefer these areas per se but because there's more space for them. Thus, high densities of bacteria are found in the filter as well as the gravel bed. In a sand substrate, the bacteria will likewise develop in the sand, though sand has even greater surface area than gravel does per volume. The caveat is that sand also restricts water movement, so if the sand is deep enough anaerobic bacteria can develop in the areas with low oxygen. Bacteria will develop anywhere.

The point of a filter, IMO, is to house both mechanical filtration and, if necessary, chemical filtration. Biological filtration in filters is an extremely valuable advantage, but is not the only point of the filter. I much prefer the idea of the waste particles being in the filter than in the tank itself, which can be rather unsightly with fish digging around in it.

Bacteria do not use high-flow areas simply due to the ammonia, but also due to the oxygen, which is the concept behind things such as biowheels. Ammonia is more or less even throughout the tank, while oxygen enters the water from the atmosphere at the surface of the water. High flow allows for better oxygen exchange, which bacteria need.

That said, I have done gravel siphons on entire tanks simultaneous to filter cartridge changes with no ill effects so that all my maintenance is in one day. On the other hand, the tanks I have are relatively lightly stocked. I do not believe that gravel siphoning physically damages bacteria very much, but I don't have experience to back that up.

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The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.

I agree that bacteria are found on every surface, but the size of the colonies is ultimately constrained by the stocking of the tank. Therefore the vast majority will be found in the filter which has the optimal conditions and those found elsewhere will be comparatively small colonies, hence my original point that the substrate can be vacced with no risk of a mini-cycle.


Mature, sensible signature required for responsible position. Good prospects for the right candidate. Apply within.

Ah, well we pretty much agree. A tank doesn't even need a substrate to run smoothly. I can't say for sure if the colonies of aerobic bacteria in gravel are substantial or not, but I do believe that siphoning the gravel won't cause a mini-cycle. Then again, I'm saying all this without experimental evidence so it might not be worth anything.

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The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.

Agreed

BTW, I think we do have the evidence from our own experiences since we've both gravel vacced on a regular basis without causing a mini-cycle.

Mature, sensible signature required for responsible position. Good prospects for the right candidate. Apply within.

Firstly, I have never had a mini-cylce happen because I vacumned the substrate with while doing a water change.

Secondly, I vacumn the substrate in the tanks with and without the UGFs.

I vacumn all my tanks, with the exception of my breeder tanks where the fry are very small. In these tanks I don't clean anything, just do water changes. As I want the detritus to build up so I will have a large colony of infusoria in those tanks, for the frys' first foods.



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There is always a bigger fish...