Weird pH Value -_-

[Koga]

Hi bro or sis,
I am into a dilemma of whether to treat tank with acid buffer or not.
I have a bunch of neon tetras, rummy nose tetra with other tetras and amano shrimp and plants
For what I understand these tetras prefer acidic water.
Tested the pH value gives a reading of 7.6, it could be more as indicator hits the high limit (API indicator).
Its weird that with driftwood, black water conditioner, and DIY CO2, the water is still alkaline.
What is happening? Could someone please advise?
Should I treat the tank with buffer?
Thanks!

[Shadow]

what substrate are you suing? any rocks inside? filter media?

[Koga]

No idea what brand of substrate were used as it was purchased decades ago.
Looks like what is in the image.


Substrate: Unknown
Fertilizer: JBL 7 balls, Seachem Flourish, Seachem Iron
Conditioner: Seachem Prime, AZOO double black water
Rocks: Looks like volcanic rock (5x palm size to tie moss)
Filter: Atman 3 DF-1300
Whats in the filter: Plastic balls, ceramic ring, filter wool, sponge filter, activated carbon, OF Zeolite Crystal

[felix_fx2]

Hi,

Looks like normal aquarium gravel. Could be your rocks and the gravel that is changing your parameters.

[Koga]

Planning to get a group of neon tetras as the previous batch (100+) mysteriously died after rearing for half a year.
Rummy nose are doing well and shoaling This is so weird.
Should I use acid buffer or neutral regulator at pH 7 or just leave it as it is?

[felix_fx2]

Koga how big is the tank in question.
Tank dimensions:
Neon: 100+
Rummynose:

The old batch didn't dissappear overnight correct. That would be really weird. If your unsure if your gravel will alter ph/gh, do the vinegar test on a small amount.

My guess is they could be granite (just a very wild guess.) but the neons disappearing could be linked to something else.

[Koga]

Tank dimension: 4 ft x 1.5 ft x 1.5 ft
Got Seachem Ammonia Alert: Its always in the 'Safe' zone (<0.02ppm), it does reaches 'Alert' (0.05ppm) when I will do a 20% water change and put it back to 'Safe'

Neon: 7 (previous batch 100+ all wiped out, put 7 to see if they are alright, been a week doing good so far)
Rummynose: ~30
Amano Shrimp: 8
Black Neon: ~20
Other minorities (all are tetras): Adds to ~20
Only neon tetras died mysteriously, it last over 2 weeks, day and night, starts with 1-2 deaths per day, then 3-4, and keep increasing until the last one died. Highest number of death in a day is 10.
Very rare death of other habitants noted.

Sounds like a contagious disease affecting only neon tetras, isnt it?
Vinegar test: Fizzing sound and tiny bubbles seen. What does it suggest?

[felix_fx2]

My humble suggestions.

Buy in smaller batches for the next one. Maybe 50 or so. Sometimes the ones delivered are not in really good state and die off pretty soon. The least it will be easier to see if any sick ones and remove them.
personally I do feel neons are weaker when delivered to lfs. Have seen them with white spots and other problems.

IMO, don't stock too much fish. If their already weak and live on like that. Good chances are 20% or more will not be able to take it and die from illness.

Seldom see folks use that. Most folks use liquid test kits. I myself only have the ph/gh test kits.

Btw, my bad. The vinegar test is to check if your gravel will affect water conditions or not. More commonly used for checking if the gravel for shrimp tanks.

[Koga]

Thank you very much for the advice.
I have been using API pH test kit.
Tap water de-chlorinated shows ~7.4 (somewhere between 7.2 and 7.6)
However the fish tank has hit the highest limit of 7.6 on the indicator.

Would you recommend that I use Neutral Regulator to make it to pH 7.0 or acid buffer? Or should I just leave it as it is?

[wongce]

if you want to reduce tank PH safely and gradually, i would suggest you to use ketapang leaves, black water extract, peat moss instead of those buffers which can cause PH shock. Your PH is still not too bad for tetras, . i kept 50 neon tetras,FR,amano at PH7.5 without any problem except occasional Kamikaze fish aka jumper (salted fish)

the problem of dying tetras may caused by their existing condition as per what Felix highlighted or it may due to old age, did you buy those BIG/XL version of tetras? some are just too old and lfs may sell them at a bargain.

In addition, your shrimps are alright? shrimps generally are more sensitive to water parameters than fish. Secondly, did your rummy nose fish shows lack of redness? normally rummy nose is a good indicator for water parameters, they show their health with colors...if full red, it means good, pale red..means something is wrong with your water....

[dc88]

how dense are your planting ? can show a full view of your tank ?
how is your filtering system ? Does the water surface agitated ?
I can only guess, if is not the substrate causing the water parameter change, than it could be not enough CO2 (since you mention DIY CO2).
Don't underestimate plants can drive the PH up very much very fast by consuming the CO2, when under good lighting.

[Koga]

Here is the overall view of the tank. Sorry for the poor quality of picture. I am only allowed 1MB.

4 feet tank with 1x T8 38W AQ underwater light.
Low light tank with DIY CO2. Yes, water surface agitated. Aerated tank and got a Aquarium Fan running on surface to cool my tank.
Plants: Vallisneria, Naja Grass, Java Fern Narrow, Laced Java Fern, Java Moss on coconut husk, Egeria Densa, Hornwort


Here are the Rummies.


A Cardinal with Black neon and Rummy nose


Some other tetras, with my Neon (put 7 neon/cardinal as "lab mice" if nothing happens I will add more neon)

This is my first tank setup, I am still a noob here. Comments are welcomed. Thank you.

[Koga]

Oh and could someone help me ID this plant? I got it from C328 but have no idea what is that. Thank you

[dc88]

"4 feet tank with 1x T8 38W AQ underwater light."

Is that the only light you have for this 4ft tank ? I try to estimate how much light level you got, but not familiar with this "underwater light" design how this compare with the typical wpg rating.

My guess is very likely not enough CO2 since your CO2 is DIY and also you aerated your tank (with air pump ?), which could drive away the CO2 in the water to the air.

When your plants use up CO2 in the water which will then drive the PH up.

How do you add the CO2 to the water ? With a reactor or diffusor ? Want to know how efficient is your CO2 injection. And what is the KH of your tank water ? PH will be very unstable if KH is low (e.g. < 3)

[Koga]

Wpg would be 38/50 -- 0.76, if I am not wrong.
Yes, have Air pump to aerate the tank.
Maybe I should add another bottle of DIY CO2.
About 1 bubble per second on the counter.
Got ceramic diffuser to diffuse the CO2, tiny bubbles seen exiting from the diffuser and disappeared before reaching the surface of the tank. (Should be a good sign i suppose)
Did not test for KH.

[dc88]

You can try 2 bottle of DIY CO2 but start the fresh bottle 3 days apart. So that when 1 bottle running out of steam the other one make up for it overall will be more constant.
Do you areate the water 24hrs/day?
Try aerate only at night when the light are off (using seperate timer than the light).
But than again your light level is so low and fish stock looks relatively high than the plant mass, the water should tends to be acidic instead. May you can check the GH and KH of the water to find out more.
The substrate (unkown??) may be the suspect as well.
BTW get the API KH/GH test kit 2-in-1 is more econmical.

[dc88]

Forgot to mention, you should check the KH of the tank water before deciding to add more CO2.
If the KH is too low, more CO2 may harm the fish. I usually adjust the water to 4degree KH. I use 2 bottle of DIY CO2 on a 80L tank, no aeration, with surface skimmer to help gas exchange, one DIY CO2 is vent off at night.
(connect to a diffuser drive by a small power head on timer). Light is 72W (3.6wpg).
PH stay around 6.2 to 6.5.

[Koga]

Thanks for the information.