How To Change Ph

[discus dreamer]

Can anyone help with this?
I have read bits here and there such as on the pinned topics about not using chemicals to shift the PH of a tank, but how do you change it?
I have one large tank 220L and the Ph is usually around 7 but it seems to creep up and at the moment is about 7.3. Early on I was loosing neons and discovered that it was 7.4 so I did use 'Ph down' and it did eventually move to 7 and the remainig neons and everyone else is fine.
I have another small tank 65L which is kind of a quaranteen tank except that my betta lives in it all the time because he attacks some of the fish in the big tank. At the moment I have 10 neons in there that I want to move to the big tank but the ph in the small tank is very low 6.4. Obviously i could just add water from the big tank to the small to start getting them used to it but would rather have both tanks at a safe level not too high and not too low.
The big tank has an external filter, sand and gravel, Co2, plants, 3 pieces of bog wood.
the small tank has an internal filter, gravel, co2, plants, small clay flowerpot.
The Ph in the small tank was 7 soon after I set it up but has dropped in the last week. I did a 20% water change but this made no difference.
Any ideas
DD

 

[4ftguppy]

Unless you are trying to breed something I wouldn't bother too much. Many aquarium fish are acclimated to higher pHs - its only breeding that needs the low values.

Remember acidic water is often soft - alkaline often hard. If your water is rock hard, getting it acidic will still probably not be what the fish want, if they like it soft.

Your neons did not die from the wrong pH. They will do fine in alkaline water - just won't breed.

If you are really keen to breed, get an RO unit (or collect rainwater) and make the water up as you need it. This water will be soft, and can be made to a required pH far more easily that hard tap water can.

Adding chemicals to water to change pH is just too unpredictable. Often they contain phosphates etc (algae problems) or change other parameters wildly

You can filter with peat of course, but its all an awful lot of work, for not much gain - and your water will go dark. You can add Hydrochloric acid too, but I'd use RO or olive without every time.

 

[discus dreamer]

thanks
that helps me to stop worrying. I live in a soft water area and would like to keep discus eventually but am just starting out at the moment so trying to learn as much as possible. I will probably swap some water from the big tank to the quaranteen tank before moving the neons.
DD

 

[black angel]

You should test your kh and gh as these are the buffers that keep your ph stable. I think im right in saying that ph fluctuates at certain times of the day as well