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Reducing PH with chemicals.

1442 Views 10 Replies 9 Participants Last post by  Glouglou
I have been thinking about dosing my weekly water change with a PH reducing chemical, but I have heard that they are not very reliable and the effects fade quickly. Does anyone here use chemical products to lower their PH? I would appreciate some input weather or not these products are worth using.

My LFS only caries Hagen PH down and Kent Marine low range controller, which Is what I think I will try.
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How high is your pH? Mine runs close to 7.8 out of the tap due to high hardness, and most plants grow fine for me.

Also, if you don't want to do this with CO2 (something plants need), why not do your WC mixed with RO water to cut the pH down?
My PH out of the tap is 8.6. Right now by using my DIY CO2 and using peat as a filter media I have been able to lower it to 7.4. But I am keeping German rams and they prefer 6.5 from what I have read. Even though they are very healthy, I would still like to see if I can reach their optimal PH level. I am also trying to achieve a black water style aquarium and I plan on keeping more low PH fish, so I just think it would be more beneficial to have a lower PH.

I am planning on building a new CO2 reactor however, so perhaps I will wait to see what happens to the PH when I build my new reactor.
KH is far more relevant and important for fish than pH when using CO2 etc.

Adding CO2 changes pH, but does nothing to the KH/GH.

Tom Barr
Why try to fix somthing that is not broken? If your fish and plants are healthy and doing well with your current parameters than there is no need to try to alter your ph with "ph down" type products.

The general concensus seems to be to either work with your regular tap water as it is or invest in an RO unit for water changes. Not chemically atlering your parameters.

As you can attest to with your healthy rams, most fish are able to live well in a wide range of ph as long as they are acclimatised to it.

By using chemicals to lower the pH you will lower the pH. However you will have very high TDS. And the TDS is one factor in keeping these fish.
If you want to lower pH the natural way, use peat but you also have to lower the KH/GH. Don't use chemicals to lower your pH, it just causes all kinds of problems in the long run.
Just be patient and change it slowly, Adding more peat to the filter will drop the pH further but you have to reduce the buffering capacity or carbonate hardness (KH) first. and stay away from changing the pH chemically.

This may help you out or at least help you try to understand what's going on.
your best solution would be to mix in ro/rodi with your water changes. as said already you want lower tds for the fish.
your best solution would be to mix in ro/rodi with your water changes. as said already you want lower tds for the fish.
Agreed. Rams IMHO are more likely to spawn in low KH/TDS water than low pH/high TDS prepared treatments. Do you have a store that sells RO/DI by the gallon?
Sorry, I forgot about my post for a little while, been a busy week...

I don't think I will buy any chemicals to lower my PH any further and I have already added peat to my filter media, but I think I will soon remove it and start filtering my water changes through a peat bucket before adding it to my aquarium. Seems to me that would be the best way to use peat affectively and get consistent results, I have also read the same.

I was looking at a bottle of Tetrafin black water extract at my LFS that boasted all sorts of B vitamins and PH buffering capabilities, I thought about buying it for the purpose of adding it to my water changes but I was unsure if it was worthwhile. I don't think I will bother, but I am curious.

I have also been thinking of adding a small amount of RO water to my water changes. That seems like it would be the best way to effectively control your water parameters and cost effective too. Would that lower my TDS, GH and PH? Anyone have any tips for adding RO water?
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Lower PH

As Chemical, You can use
No Phosphates. (Sulfuric acid)

Any acid add to the tank will reduce and transform the Carbonates (KH) in carbonic acid

The best way is By keeping your KH low (Osmosed water) filtering on peat, adding CO2
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