Ph Levels Question

[Miss M]

Hi everyone. My 40 gallon tank ph level is reading 7.6, according to the dropper test. I tested my tap water, and that level registered at 6.8. Do I need to be concerned with the tanks high reading?

It's stocked with: 7 zebra danios, 6 neons, 2 glowlights, 1 molly, 2 platys, 2 guppies, 3 black tip tetras, and 3 corys.

Approx 40% water changes are performed every other week. Water is treated with dechlor and a little aquarium salt (I stir up the gravel/salt before the cory's go over it).

no ammonia, nitrite, and nitrate is 30, as of last reading.

Thanks for any suggestions.

Miss M

I know I should have more glowlights, but 3 of the 5 died w/in 48 hours of adding them to the tank. That was about 1 month ago.

 

[ktricky]

thats about nutral and is what most fish like to be at

 

[Miss M]

Thank you. I just wanted to make sure.

Miss M

 

[Squid]

It does seem a little odd that the two are different. I would be tempted to test them again as these tests can be a little off.

Now.. i do remember reading something about tap water reading a little different if you do the test straight after pouring it. Something to do with the gases in the water at this point which may affect the reading. You could try taking the water from the tap as a couple of samples and leave them to rest and the gases to diffuse. Test one after a couple of hours and one after say 12-24 hours and see what the results are. These samples will give a more accurate reading, with no other influences.

Differences between tank water and tap water do occur though, as the tank water can be affected by other things in the tank. Bogwood is known to lower the PH, and some rocks and coral sand has been known to higher the PH.. Highering the PH using rock is often done by people wishing to keep Mbuna in higher PH conditions.

Once you have established/confirmed what the PH of the tap water is, we can then look at the PH swing that would occur when doing a 40% water change, and see whether it is too high for the fishies health.

The PH level of the tank after a water change using your current stats is 7.28ish (hehe), which is a PH swing of a little over 0.3. I'm not sure what is ok and what is not, but i'm sure 0.3 wouldn't be much of a problem anyway.

Perhaps one of the more experienced peeps could let us know if I am talking absolute garbage, but this is just my understanding.

Squid

 

[Miss M]

Hi Squid. The test from the tap water was taken immediately, so maybe the numbers are not accurate, as opposed to letting the tap water sit for a while (which I am going to do now).

I'll also test the tank water a few hrs after I do a water change. Would 40% be too much? I like to make sure I get all the gravel really good, and by the time I do, I've taken out about 40% of the tank water. I figured doing this every other week was ok, but maybe I should do only approx 25% every week? Let me know what ya think.

Miss M

 

[Squid]

40% is a fairly high water change, but is done weekly by people in the Planted Section who have hi-tec planted tanks using the EI (estimated index) method of fertilisation. I tend to do mine every couple of weeks instead of every week, and I do about 25%. The frequency and amount should be partially governed by the nitrate levels in your tank. I keep mine pretty low, but that is helped by me having a good number of real plants in the tank, which use the nitrates.

I have heard people mainly try to keep the nitrate levels below 50ppm, but i tend to keep mine between 10-20. The level of stocking of fish in your tank will strongly influence the level of nitrates of course. Is your reading of 30ppm before or after a water change?

Squid