Since I am mixing my R.O. water with tap water and still not getting as low of a pH as I want, would a pH down product be more effective as lowing my pH safely and keeping it down, considering I won't be fighting against the buffering capacity as much?
pH down more successful in water with low TDS
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rich311k
Aquarium Advice Addict
Do not use chemicals. Just up the amount of RO in the water mix.
roka64
Aquarium Advice Addict
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Moving to FW Discussion section.
travis simonson
Aquarium Advice Addict
RO water is basically pure water: pH ~7.0, KH 0, GH 0, TDS ~0. It has no buffering capacity so its pH is easy to alter and is subject to large fluctuations. For best use it needs to be remineralized by adding carbonates for KH, and other salts (sulfates, chlorides, etc.) for GH, bringing each of these measurements up to at least 1 dKH and 1dGH.
Using a pH lowering product can be dangerous without at least one degree of KH/buffering capacity as it can cause a large drop in pH. I also don't suggest any of the standard pH lowering products because most of them use phosphates to decrease pH and can create algae problems due to the large increase in phosphate levels they cause. Seachem's Acid Buffer is an excellent alternative to bring down pH levels, although it will also decrease KH levels commensurately, so be prepared for this. It does not use phosphates and thus has no effects on algae growth.
Hope this helps
Using a pH lowering product can be dangerous without at least one degree of KH/buffering capacity as it can cause a large drop in pH. I also don't suggest any of the standard pH lowering products because most of them use phosphates to decrease pH and can create algae problems due to the large increase in phosphate levels they cause. Seachem's Acid Buffer is an excellent alternative to bring down pH levels, although it will also decrease KH levels commensurately, so be prepared for this. It does not use phosphates and thus has no effects on algae growth.
Hope this helps
Well, the pH of my R.O./D.I. water is far below a 7. My pH test kit goes down as low as 6.0, and my R.O. water is no higher than that. Like you said, the TDS etc. is 0, but the pH is not a 7. So you're saying that having a GH of 1dGH and 1 dKH are acceptable parameters? If that's the case, then I can probably mix a gallon to a gallon and a half of tap to 3.5-4 gallons of R.O. The problem is, I was under the impression that I should be shooting for a KH of at least 4, and a GH of well, I don't know, 2-3? To get those results I need to mix more tap with my R.O., and when I do, my pH shoots up too high.
I understand that chemicals are not the 'answer,' but if my TDS is around 3-4 dKH/GH, wouldn't a pH down work much more effectively and be much safer in terms of stability (since there is less buffering capacity in the water)?
On a similar note, when I was buffering my water with additives, I was using Kent R.O. Right and Sodium BiCarbonate. The reason I abandoned this was that the Sodium BiCarbonate would raise my pH too high, and I recently read an article where someone claimed the same thing happened to them (implying that carbonate buffers raise the pH too high) and that this person switched to Seachem Alkaline Buffer. Has anyone used this product and had better luck at keeping a low pH while still adding some KH?
I understand that chemicals are not the 'answer,' but if my TDS is around 3-4 dKH/GH, wouldn't a pH down work much more effectively and be much safer in terms of stability (since there is less buffering capacity in the water)?
On a similar note, when I was buffering my water with additives, I was using Kent R.O. Right and Sodium BiCarbonate. The reason I abandoned this was that the Sodium BiCarbonate would raise my pH too high, and I recently read an article where someone claimed the same thing happened to them (implying that carbonate buffers raise the pH too high) and that this person switched to Seachem Alkaline Buffer. Has anyone used this product and had better luck at keeping a low pH while still adding some KH?
Also, I am aware of the phosphate issue, and it sucks. The buffering capacity of my current mix of R.O. and tap-like I said above-is 3-4dKH/GH. Isn't that enough buffering capacity to add a small amount of pH Down and have it work safely?
Sorry, I see you noted the Seachem Acid Buffer. That sounds like a better option than the pH down since it is phosphate free. If my KH is 3-4 degrees, how much of this Acid Buffer should I use? I guess not much because I don't really want to drop my KH below a 2...
SpeedEuphoria
Aquarium Advice Addict
I'm confused, why not take the easy route and just use more ro water to tap? use no chemicals?
Ok, I am glad you just said that, SpeedEuphoria. I am currently doing a mixture of R.O. and tap water in my basement in a 5 gallon bucket. I have added one gallon of tap, and the bucket is still filling the rest of the way up with R.O. My pH is currently about a 7 (which will rise as it sits out) but the real problem is that when I test my GH, it barely even registers. I am currently out of KH test, but I can guarantee that my KH won't register as much either.
I WANT the mixture to be more R.O. than tap, but when I use mostly R.O., I barely have any hardness at all. The only way to get my pH down is to use mostly R.O., but then I am left with almost no KH and GH, and that is what I am concerned about. Should I just 'not worry' about the KH and GH levels?
This is why I think a mixture of half tap and half R.O. would be better. My pH would be higher, but my KH and GH would still be present in the 2-4 degree range, and then I could add a little ph Down to lower the pH.
My pH WILL NOT LOWER without sacrificing GH and KH.
I WANT the mixture to be more R.O. than tap, but when I use mostly R.O., I barely have any hardness at all. The only way to get my pH down is to use mostly R.O., but then I am left with almost no KH and GH, and that is what I am concerned about. Should I just 'not worry' about the KH and GH levels?
This is why I think a mixture of half tap and half R.O. would be better. My pH would be higher, but my KH and GH would still be present in the 2-4 degree range, and then I could add a little ph Down to lower the pH.
My pH WILL NOT LOWER without sacrificing GH and KH.
Now I just added another half gallon of tap to the 5 gallon bucket. These rest is R.O. and it is filled. The pH is reading a 7 (which will rise after it sits out) and my GH is barely registering. So you see, just to get my pH to NEAR a 7, I have to sacrifice GH and KH to do it.
Now, if I were to mix, lets say 3 gallons tap/2 gallons R.O., my pH would obviously be much higher, but at least I'd have some GH and KH there, and I could then drop the pH a little by added pH Down, since I have the KH to play with, but I am simply not sure what to do.
Option #2 seems to make more sense to me, even though I'd be using a pH down.
Now, if I were to mix, lets say 3 gallons tap/2 gallons R.O., my pH would obviously be much higher, but at least I'd have some GH and KH there, and I could then drop the pH a little by added pH Down, since I have the KH to play with, but I am simply not sure what to do.
Option #2 seems to make more sense to me, even though I'd be using a pH down.
Sum22
Aquarium Advice Freak
If you don't mind my asking, what the heck are you going to be keeping in your tank that requires you to have a perfect water conditions?
Well, good question. It may seem that I am trying for perfection, but I'm not. It is a combination of trying to learn about water chemistry and trying to achieve soft water. The more I learn, the better off I will be to try more sensitive species, like Discus. But really, I am just trying to figure out a standard of what I want my water to be, and sticking with it.
First off, pH and KH are linked. The majority of the pH lowering products on the market are going to reduce both. The lower the KH the less stable the pH (unless other buffers are present) so using a pH lowering product can easily destabilize the pH by removing the majority of the KH.
Secondly your tap water has a buffer other than KH which is causing the pH to be unexpectedly high. So you are trying to adjust your water so that it keeps the same KH but reduces the pH. You need to find out what that buffer is and treat it, otherwise everything you do is going to cause the pH or the KH to be adversely affected according to your goals.
Your best option is to use straight RO water and use the appropriate products to reconstitue it. You've mentioned using RO Right in another thread, but that the KH isn't being raised sufficiently. Why not add both RO Right and Baking Soda? The Baking Soda will raise the KH and therefore the pH.
Secondly your tap water has a buffer other than KH which is causing the pH to be unexpectedly high. So you are trying to adjust your water so that it keeps the same KH but reduces the pH. You need to find out what that buffer is and treat it, otherwise everything you do is going to cause the pH or the KH to be adversely affected according to your goals.
Your best option is to use straight RO water and use the appropriate products to reconstitue it. You've mentioned using RO Right in another thread, but that the KH isn't being raised sufficiently. Why not add both RO Right and Baking Soda? The Baking Soda will raise the KH and therefore the pH.
Joy--Like I said earlier at some point in all my ranting, when I added the Sodium BiCarbonate, my pH would shoot past 7, but when I tested the KH, it would barely register as me having any KH at all. Here is a sample from an article I've been reading that suggests using Seachem Acid Buffer and Alkaline Buffer:
"Carbonate buffers (which buffer at a higher pH and pretty much amounts to using full tap water again) cannot be used. Also, I like to keep my Macs in planted tanks; hence phosphate buffers (which are notorious for causing algae) are out of the question. The only product out there that are not 100% carbonate and phosphate buffers is a pair of products by Seachem called “Acid Buffer” and “Alkaline Buffer”. Used together in varying proportions, I can achieve any pH of water between 3 and 10 that I want."
Obviously, I am not the only one who has used baking soda only to have it buffer my pH far past 7. It sounds like this Seachem Alkaline buffer mayb give me some KH AND keep my pH a little lower.
I would still be using straight R.O. with the R.O. Right and the Buffer Up by Mardel if the buffer up had not kept my pH so high.
You also stated that a pH lowering product can lower the MAJORITY of the KH to achieve a lower pH, but if I only use a small amount of the pH lowering product, wouldn't it leave at least some KH behind? For example, if I had a KH of 3-4 with a pH of 7.8 and used a small amount of pH Down, how much KH would it use up?
Sorry I am a pain, but I have to get to the bottom of this. Thanks!
"Carbonate buffers (which buffer at a higher pH and pretty much amounts to using full tap water again) cannot be used. Also, I like to keep my Macs in planted tanks; hence phosphate buffers (which are notorious for causing algae) are out of the question. The only product out there that are not 100% carbonate and phosphate buffers is a pair of products by Seachem called “Acid Buffer” and “Alkaline Buffer”. Used together in varying proportions, I can achieve any pH of water between 3 and 10 that I want."
Obviously, I am not the only one who has used baking soda only to have it buffer my pH far past 7. It sounds like this Seachem Alkaline buffer mayb give me some KH AND keep my pH a little lower.
I would still be using straight R.O. with the R.O. Right and the Buffer Up by Mardel if the buffer up had not kept my pH so high.
You also stated that a pH lowering product can lower the MAJORITY of the KH to achieve a lower pH, but if I only use a small amount of the pH lowering product, wouldn't it leave at least some KH behind? For example, if I had a KH of 3-4 with a pH of 7.8 and used a small amount of pH Down, how much KH would it use up?
Sorry I am a pain, but I have to get to the bottom of this. Thanks!
Maybe what I am trying to get to the bottom of is that the people who keep soft water tanks have a low KH, correct? So these tanks require frequent water changes to add back the KH which has been used up, and because there isn't much there in the first place?
SpeedEuphoria
Aquarium Advice Addict
Obviously phosphate
