Dropping ph to 6 in a stable and moderate manner

my water parameters for my 60l tank (16.67 gallons) are:
7.2 ph
6 kh
greater than 21 dgh
I have 3 platys a hornwort and a java fern
I've started dropping my gh using 20% water changes with direct ro water.
I've decided I want to also drop my ph to around 6, how can I do it the safest way possible? also, should i use baking soda to keep my kh high so no ph fluctuations?

 

As your kH drops your pH will follow. Keep consistently tracking the changes with ro until you find the mix that gives you what you're looking for. You could test the ratio in a bucket too, I would guess somewhere around 1 part tap water to 6 parts RO, if you're tap is similair to your listed tank at 6 dKh, and if your ro is at/near 0kh. Once you're there you will need to watch your ammonia levels as the bacterial and archaean colonies adapt to the acidic conditions, it could be a bit of a mini cycle.

 

I've started dropping my gh using 20% water changes with direct ro water.

Good, do that until you are at a KH of 0°.

I've decided I want to also drop my ph to around 6, how can I do it the safest way possible?

Botanicals: Seedpods, IALs, oak leaves (or other leaves), alder cones. Might take some months to reach the desired level. Faster would be with peat.

also, should i use baking soda to keep my kh high so no ph fluctuations?

Fluctuations are not that bad. Fluctuations of 1 pH point are usually fine. The time in which the change occurs is the more important factor. 1.0 difference within 30min is dangerous, 2.5 difference within 4 hours is fine.
Humic substances from the botanicals will stabilize your pH in the low range around 5-6. You just replace one method of stabilizing with another.

Pure RO means you have to dose an all-in-one fertilizer for your plants, though.

Also one thing to keep in mind: Invertebrates like snails and shrimp do not do well in soft water because of a lack of minerals. So if you want to keep any of these you better leave things as they are.

A middle way between tapwater levels and clear- or blackwater is hard to manage, as it's a permanent balance act. So if you have the means (steady supply of RO and botanicals or peat), go full clearwater or blackwater. If not, stick to the tapwater parameters.

 

I have been using ADA Soft Water to lower my PH in my first tank because my tap water was PH8 and I used Seiryu stone on top of that for my hardscape. Worked nicely, dropped PH 1 point permanently as long as used. didn't cause any problems with shrimp, snails, fish or plants.

 

Wouldn’t platys prefer harder water though? A ph of 6 seems a bit low to me, unless they are being removed and replaced with something else?

 

Wouldn’t platys prefer harder water though?

Oh, I just saw the platies mentioned! Thank you!

In that case the water has to be hardened and the pH has to stay above 7.5.

And now I remember. galben35 with livebearers you keep the water hardness and pH high. I have written something about that in one of your other threads. Softwater fish can be kept in hard water, hardwater fish cannot be kept in soft water. There is no middle way.

 

Planted tanks experience a daily degree of ph fluctuations anyhow. Not sure to what degree a hornwort and a java fern make a difference given your tank. You could regulate the fluctuation by means of interactive CO2 injection, but for fish keeping it is not worth it. Fish can handle these fluctuations much better than most people realize.

Ah, you already mentioned this Macz...

 

Fish can handle these fluctuations much better than most people realize.

Usually yes, with livebearers and other hardwater species this is not that easy, though. If it was tetras or gourami it'd be no problem.

 

Usually yes, with livebearers and other hardwater species this is not that easy, though. If it was tetras or gourami it'd be no problem.

You have some reference? Not that I question this; just want to broaden my knowledge.

 

Research has focused on softwater species' abilities to acclimate and deal with fluctuations for the most part. Sometimes they did confirmation by comparison with hardwater fish. I can look whether I find something in English. Or are you ok with German?

Otherwise it's my experience with numerous Rift Lake cichlids I've sold over the years and confirmation from other people that bred and sold hardwater species. Whenever the customers put them in soft water (against our advice) the fishes health deteriorated quickly. I think it's not the fluctuations themselves, but the baseline levels that bring them to their proverbial knees.

Some livebearers seem to be able to acclimate to softer water, but that's not that common it seems. One would hear of it more often.

 

ok, thank you all! ill keep it around 7 ph, really no reason to drop ph (wanted a more tropical tank for future options, ill just do a blackwater tank in the future instead).
so final question, at what gh would it be ok to add neon tetras and kuhli loah? lets say i'll try to find captive bred and acclamite them with drip

 

ill keep it around 7 ph

Raise it to 7.5 to be safe.

so final question, at what gh would it be ok to add neon tetras and kuhli loah? lets say i try to find captive bred and acclamite them with drip

Neon tetras - yes. Drip or cup acclimation doesn't matter with farm fish.
Loaches will likely be wild caught, so those probably not.

 

Research has focused on softwater species' abilities to acclimate and deal with fluctuations for the most part. Sometimes they did confirmation by comparison with hardwater fish. I can look whether I find something in English. Or are you ok with German?

Otherwise it's my experience with numerous Rift Lake cichlids I've sold over the years and confirmation from other people that bred and sold hardwater species. Whenever the customers put them in soft water (against our advice) the fishes health deteriorated quickly. I think it's not the fluctuations themselves, but the baseline levels that bring them to their proverbial knees.

Some livebearers seem to be able to acclimate to softer water, but that's not that common it seems. One would hear of it more often.

If the line of reasoning is that hardwater fish have a hard time retaining minerals (as there is no need to in hardwater environments), thus will struggle in low mineral environments, then I'm following you.

 

If the line of reasoning is that hardwater fish have a hard time retaining minerals (as there is no need to in hardwater environments), thus will struggle in low mineral environments, then I'm following you.

Basically. As the hardwater habitats have more stable parameters they also have to face less harsh fluctuations.