I had sent water sample at the water testing center but unfortunately, I was told that they needed at least 240 ml sample. I will try to send another sample and will post the result later.

here is my water parameters:
September 19, 2008


Water Test Result:

Source : Personal Aquarium

Test 1 : Physical Description – clear, colorless liquid
Ammonia- nil
Nitrite - nil
Nitrate- 18
Alkalinity 5
e. coli negative
quality potable

Test 2 : Sample - moderately cloudy
pH 8
manganese 2
Ammonia nil
Nitrite nil
Nitrate 14
E.coli negative

I am surprised to have this result. I will try to get a test kit to find out if those testing center are reliable. They are authorized by the government to operate. The first result made me sent another sample to another testing center to confirm.

Hey guys!

As I have said, after testing my water and found out to be normal.... I was moved to give my fishes a new dose of water. As explain earlier, my pangasius had breath gasping for a while... until all of them to be normal.

My instinct push me further to have my water to be tested after 30% water change.

Agash! here is the result to my surprise:

Amonia Nil
Nitrite Nil
Nitrate 57.92
Alkalinity 46.66
pH 7.06

Although all my fishes are well, I am now worried the new data might give negative effect on them. I will try to figure out which one gave them bad changes: water changes with filter cleaning.

I used to clean the filter and the substrate with out changing my water;
now when I do change my water and clean the filter gave me this alarming situation.

When I do not change my water and no testing, I don't have worries. Today, I am rattled. I have to keep an eye on them and see if any sign of trouble. I have not applied salt because salt is always in the water once you applied it. It does not evaporate.

Moreover, testing my water cost me lot. Wow! I hope nothing unusual will happen to my fish. I had lost my previous fishes on calamity but not on sickness. I will not allow that.

It's OK. Readings are like a photograph, they capture a moment in time. There are variables in play that would affect our results. e.g. to accurately measure pH it is better to take a sample, leave it sit overnight and measure early in the morning; false positive readings in nitrates or even ammonia are not unheard of.

There are ways of keeping Nitrates at minimum, and in saltwater, there are ways to keep them at zero; however, in freshwater zero for nitrates is a bad thing: it means we lost the type of bacteria that brakes down nitrites. I keep my Oscars with plants in part for that reason.

I know fishkeepers that go with minimal water changes and their fish seem to be fine, even breed in there. One of them has huge Wet/Dry sump filters and keeps goldfish/koi with waterchanges every three months; for other fish he goes every 6 months.

However, I am in the opposite side: The more close to 50% the better. I do a partial (40-60%) water change every 5 to 7 days. I never vacuum the whole substrate at once. I usually do one half one week, the other one next week.

The health of my fish is the best indicator that this is good for them.

I am very careful about filtration, again, the more the better. My 121UKgal tank (72"Lx18"Wx26"H) is at floor level, so I can't have a Wet/Dry sump filter, so I use three AquaClear 110 and rinse their media alternatively, leaving a week or two in between. All have extra sponge and Activated Charcoal (the only media I change every 3 weeks, if I have no replacement bag I leave that filter without charcoal).

Inside my tank I have a DIY powerhead with a canister ( filter fiber inside ) attached, placed at the lower end in the Oscar's territory to aid in mechanical filtration.

I also have a submersible 18W UV sterilizer, just requires replacement of the UV lamp every 6 months. Other than that plants help me a lot. I have slowly managed to go from lightly to moderately planted.

My readings (yesterday, before water change)
pH 7.6
Ammonia 0
Nitrite 0
Nitrate <25 ppm
13dGH, 8dKH

Note: I began filtering through peat yesterday, aiming at pH 6.8, KH> 2dKH.

Pepe
Santo Domingo

after several days of monitoring, all my fishes are well.
my new tank for the pangasius was broken when the white
one banged it hard with the head. they are now back to the
original tank.... very crowded.

i am now in the process of comparing data with the open filtering
box as against the closed system. i do believe that open box is more
efficient in controlling the presence of ammonia and good bacteria.

I'm curious to hear more about how you're testing your water. I know of no conventional method to accurately measure nitrates to the hundreth of a ppm, which is implied by the results you reported above (57.92), which makes me suspect the technique of measurement. Even photometric measurements will only commonly give accuracy to the tenth of a part per million. Further evidence to question the testing method comes from your nitrate spike after a water change. Generally, this is evidence of ammonia and nitrite levels affecting the nitrate test to desensitize it to inaccurate levels, which would mean you had a false negative test for these parameters earlier.