pH Adjustment (pH down?)

[Milliardo Peacecraft]

My tap water is typically around a pH of 8.4 straight out of the tap and I've found that my plants seem to do better if I get the pH down to something below 8.0, anything 7.5 to 8.0 seems to be just fine.  Over the past couple years I've been adding a set amount of pH down to the water every water change to get the water a bit below 8.0.  I was wondering if anyone had a suggestion of a better way to accomplish lower the water pH to something below 8 that would be simpler than chasing it with pH down.

[Lonkley]

Do you have a water softener? If so can you get a bypass on it and see what the water actually is? Whatever is softening could raise it.

You can also add driftwoods, i think their tannins will cause the ph to drop. 

You can go heavy into plants, if you haven't already.  Add CO2.

You can mix your water with reverse osmosis water. Maybe start with 10% increments so you don't crash it quickly, you can get some from your LFS probably, and if it works you can get a small system for your house or just periodically fill a 5 gallon container. 

Also, Depends how big a tank I guess, probably easier to do in a 40g than a 200g.
 

[Mmiller2001]

Easiest way is to cut your source water with distilled water. It will lower GH also and I would test GH so you have a baseline established.

Edited December 4, 2023 by Mmiller2001

[Milliardo Peacecraft]

@Lonkley I do have a water softener running.  The hardness here in Rock County Wisconsin is about 330 mg/L so the softner is working pretty good to take care of that amount of hardness.  I do have a few small pieces of driftwood in my 75 gallon aquarium, mostly used to anchor various Java ferns (standard and windelov).  

I do use Seachem Equilibrium in the softened water to restore some of the minerals without getting to the point of having the water lime up everything with hard water deposits.

I have debated about adding CO2, if I had more time in life, I totally would do it, just to tinker around with it, even if the plants I have don't really need it.  How much does CO2 bring down the pH of an aquarium?

[Lonkley]

On 12/4/2023 at 11:16 AM, Milliardo Peacecraft said:

I have debated about adding CO2, if I had more time in life, I totally would do it, just to tinker around with it, even if the plants I have don't really need it.  How much does CO2 bring down the pH of an aquarium?

It depends on your water. I think math is involved between the KH and the amount of CO2 you use. Also you can't add so much CO2 as to suffocate your fish.  You would have to look it up. Or maybe someone else knows some guidelines.

 

[Mmiller2001]

A 1 to 1.5 pH drop will put you into the desired 30ppm CO2 range.

[tolstoy21]

On 12/4/2023 at 1:27 PM, Lonkley said:

Do you have a water softener? If so can you get a bypass on it and see what the water actually is? Whatever is softening could raise it.

A water softener will reduce the mineral hardness of water, but won't affect alkalinity.  If it did have an affect (large or small), that affect would be to lower the Ph not raise it as it doesn't contribute minerals or carbonates to the water.  Typically the impact a water softener will have on household water is to add sodium in negligible amounts. 

However, if you do have a household calcite filter like this --> example calcite filter <-- it can boost your Ph pretty high for a duration (that's its intended purpose).

As others have suggested, the best way to lower your Ph is to use rain, RO or distilled water. In my experience, botanicals will only get you so far and won't put a meaningful dent in a Ph above 8.

Believe it or not you can also lower Ph pretty easily with muriatic acid (which is just a slightly weaker form of hydrochloric acid), but you do have to really understated the dosage before attempting to use it (who would have thunk it, acid will acidify water!). But honestly, in the end, the net effect of that is probably the same as using Ph down.

Edited December 5, 2023 by tolstoy21

[Galabar]

I find it much easier to tear down and then build back up.  You might consider an RO unit.

Also, could you share your GH and KH measures?

[nabokovfan87]

On 12/4/2023 at 10:13 AM, Milliardo Peacecraft said:

I was wondering if anyone had a suggestion of a better way to accomplish lower the water pH to something below 8 that would be simpler than chasing it with pH down.

Use an active substrate, wood and botanicals, as well as a product like seachem acid buffer.  There is also peat moss balls that you can use in filtration.

[Milliardo Peacecraft]

@Galabar my aquarium water quality numbers are below:

75 gallon aquarium, Nitrate: 10 ppm, Nitrite: 0 ppm, GH: 150-300, KH: 180-300, chlorine: 0 ppm

So far I've found that if I do a 1/3 water change I can put in 40 mL of pH down and the water will end up being between 7.5 and 8.0 pH.

[Galabar]

This? https://www.1000bulbs.com/pdf/gh-ph-down-msds.pdf

 

[Milliardo Peacecraft]

@Galabar

Yep, that looks like the SDS for the pH down that I use.