Let's just say the rise in TDS is just fish waste slime/poo etc, and not food spit out, in a fish only tank, any opinion on what the max TDS difference should be for a healthy aquarium?
Nitrate Testing Accuracy (false high readings) & Water Change Implications
- Thread starter NW Cichlid Keith
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Let's just say the rise in TDS is just fish waste slime/poo etc, and not food spit out, in a fish only tank, any opinion on what the max TDS difference should be for a healthy aquarium?
I agree with you about conductivity, the only problem is a normal aquarists is usually not able to determine conductivity/TDS, because there really are no down and dirty (inexpensive) kits or ways available to test for it.
I would check mine weekly because I had a conductivity meter in the lab where I worked.
And although my nitrates tested low, the conductivity of my tanks was normally rather high.
This is the reason I kept the species I did. Many Central American bodies of water can be rather high, with the incursion of sea water, and limestone substrates, and many of those species can handle the mineral content, as compared to South America e.g .
And may be one of the reasons I had trouble with spawns from some Malagasy species like Paretroplus.
I went back to some of my log books to check.
As you can see I was quite anal about my water quality testing.
I do believe nitrate is only part of the problem, but the ability to test for it, also indicates the symptoms of the other less than desirable aquarist practices.
If an aquarist overfeeds, over stocks, or simply puts too big a fish in too small a tank, high nitrate will normally be the obvious result.
I would check mine weekly because I had a conductivity meter in the lab where I worked.
And although my nitrates tested low, the conductivity of my tanks was normally rather high.
This is the reason I kept the species I did. Many Central American bodies of water can be rather high, with the incursion of sea water, and limestone substrates, and many of those species can handle the mineral content, as compared to South America e.g .
And may be one of the reasons I had trouble with spawns from some Malagasy species like Paretroplus.
I went back to some of my log books to check.
As you can see I was quite anal about my water quality testing.
I do believe nitrate is only part of the problem, but the ability to test for it, also indicates the symptoms of the other less than desirable aquarist practices.
If an aquarist overfeeds, over stocks, or simply puts too big a fish in too small a tank, high nitrate will normally be the obvious result.
I agree with you about conductivity, the only problem is a normal aquarists is usually not able to determine conductivity/TDS, because there really are no down and dirty (inexpensive) kits or ways available to test for it.
I would check mine weekly because I had a conductivity meter in the lab where I worked.
And although my nitrates tested low, the conductivity of my tanks was normally rather high.
This is the reason I kept the species I did. Many Central American bodies of water can be rather high, with the incursion of sea water, and limestone substrates, and many of those species can handle the mineral content, as compared to South America e.g .
And may be one of the reasons I had trouble with spawns from some Malagasy species like Paretroplus.
I went back to some of my log books to check.
As you can see I was quite anal about my water quality testing.
I do believe nitrate is only part of the problem, but the ability to test for it, also indicates the symptoms of the other less than desirable aquarist practices.
If an aquarist overfeeds, over stocks, or simply puts too big a fish in too small a tank, or doesn't do enough water changes,high nitrate will normally be the obvious result.
I would check mine weekly because I had a conductivity meter in the lab where I worked.
And although my nitrates tested low, the conductivity of my tanks was normally rather high.
This is the reason I kept the species I did. Many Central American bodies of water can be rather high, with the incursion of sea water, and limestone substrates, and many of those species can handle the mineral content, as compared to South America e.g .
And may be one of the reasons I had trouble with spawns from some Malagasy species like Paretroplus.
I went back to some of my log books to check.
As you can see I was quite anal about my water quality testing.
I do believe nitrate is only part of the problem, but the ability to test for it, also indicates the symptoms of the other less than desirable aquarist practices.
If an aquarist overfeeds, over stocks, or simply puts too big a fish in too small a tank, or doesn't do enough water changes,high nitrate will normally be the obvious result.
Personally, I don't let the TDS rise beyond 10-15 ppm difference with my tap. Having said that, I don't fret over a bit of an extra TDS reading because I know myself and I'll certainly not let it go any further, and do the extra water changes to get it down once I get the extra time. It is not difficult to do, drain down to fin level a couple of times and its done....Then carry on as before as long as the TDS stays in line with whatever you've decided is your base measure. Mine is tap water and that's what I advise people use as base measure but if one doses inorganic fertilisers or has rocks that harden the water, then the base measure will be higher than the tap. Point is, the TDS rise should not be from biological processes due to fish waste...
The overall TDS trend has to be very close to your base measure, never let it rise gradually over months/years....That's how people let things deteriorate..in time...One is never as enthusiastic as when first setting up a tank.....and if one is in the hobby long enough, they certainly have those "down" moments more often than not....If your stick to that TDS base line, you and your fish will live through it
TDS meters for hobbyist are quite inexpensive now, in fact for quite a few good years. One can buy one for 30-50 quid and use it for years... I bought my latest one for 30....TDS meters in fact measure conductivity really, i.e. dissolved ions rather than total dissolved solids but use a conversion factor to ppm(TDS) if one prefers ppm, which I do..by habit. The conversion factor is normally 0.64 but some more expensive meters have 2-3 conversion factors to arrive from a conductivity to a TDS reading.
Point is, you don't need an expensive one. Measure conductivity rise which a cheap conductivity meter will measure rather accurately. The actual base line, i.e. tap water conductivity is irrelevant. Once you've put those fish in your water, the minimum conductivity they'll get is your tap/well water or whatever water you're using for water changes, and providing you can drink that water, its good enough for fish too. I advise concentrating one's energy on the "rise" of TDS/conductivity. Its as simple as 5-3=2. Almost all my fish come from black water habitats, all of them are living healthily for years in hard but clean tap water.
I believe you, ha, ha. What would be your average TDS/conductivity rise though if you take one tank as an example, in relation to nitrate reading...
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My source water was Lake Michigan, and before treatment the lake has a TDS averaged (aggregate of minerals) 176 mg/L to over 300mg/L depending on the season, but after treatment for drinking potability, much higher at times 500mg/L.
I changed about 40% on each tank every other day, could go from 600mg/L after, to over 3000 before a water change.
I changed about 40% on each tank every other day, could go from 600mg/L after, to over 3000 before a water change.
That sounds like an awful lot of a rise?
I once let a tank without water changes for 5-6 months, TDS doubled in the tank over the period. The tank was heavily planted, above and underwater, and the actual nitrates I measured were 10-20ppm only if I were to believe my nitrate test as the fish were acting rather unhappy. A couple of the fish got sick so I figured its time to stop the wild experiments......That's the last time I ever let the TDS rise in any significant amount...
I once let a tank without water changes for 5-6 months, TDS doubled in the tank over the period. The tank was heavily planted, above and underwater, and the actual nitrates I measured were 10-20ppm only if I were to believe my nitrate test as the fish were acting rather unhappy. A couple of the fish got sick so I figured its time to stop the wild experiments......That's the last time I ever let the TDS rise in any significant amount...
