PH Issue, need some help figuring this one out.

[Cook.MN]

Tank #1 PH: 8.2
Tank #2 PH: 8.2
PH out of the Tap: 7.6

Tank #1 has Eco-Complete African Cichlid Sand Substrate and black lace rock.
Tank #2 has Eco-Complete Plant Substrate, 2 large pieces of driftwood both over 20 inches and is a planted tank.

How on earth did Tank #2 get that high of a PH?

Any help on lowering the PH on Tank #2 would be great, I would prefer it to be around 7 but could easily live with something in the 7.5's. Also, would buying water from the grocery store help with this? I "thought" I had read something regarding this but now I can't find the thread.

I want Tank #2 to be a SA cichlid/community tank but with a PH of that high I won't be able to do that.

[Darkblade48]

Have you tested the pH of your tap water after allowing it to sit for 24-48 hours? There is dissolved carbon dioxide in tap water that may be giving you lower than expected readings.

Also, as you mentioned, you could use DI or RO water in your water changes in order to lower the pH slightly, though it may get expensive if you are going to continuously purchase it from the grocery store.

[Cook.MN]

I haven't tested my tap water after I let it sit for 24-48 hours. Where I live it's known for hard water that's why the african cichlid tank was so easy to get a high stable PH. I would have thought between the plants and the driftwood that it would have helped with getting a lower PH.

I do believe it's entirely my tap water, just baffles me that I have the eco-complete sand substrate made for african cichlids that's suppose to help raise the PH and as it turns out it's the same PH without that substrate. I'm going to do a large water change in tank #2 tonight with some distilled water to see if that can help.

I don't like using chemicals so I don't want to use PH down, if I can do weekly water changes of 10% and refilling that with distilled water that would be fine.

[imeridian]

The use of pH altering chemicals will only lead you down a road of frustration, put the thought out of your mind. It's also pretty futile to worry about the pH, but as Darkblade mentioned, if you want to actually lower the KH of your water, which will reduce the pH as a side effect, you can do that by using RO water. The key here is that you can't add something to your water in order to remove something.

FWIW, regular Eco Complete bumped my KH and GH up a couple of degrees in pH 7.0 tap water, that's very likely what you're seeing. That effect wears off though, but in my case it was a desired effect.

[Cook.MN]

I'm going to try some peat moss, question is do I need any special kind that's aquarium safe?

[lauraleellbp]

You want Canadian peat moss, and 100% moss, no additives.

WalMart carries 100% sphagnum moss.

Peat won't take much out of your hardness, however- mainly lower the pH plus add tannins to the water.

[spinycheek]

If you have a lot of plants (or algae) and no CO2 injection the pH can rise that much. If you don't mind a yellow/brown color in your water, peat and some driftwood works well. I had the same problem and adding CO2 with a yeast/sugar reactor brought the pH back down.

[jaidexl]

What is the tap's KH and GH? I'm guessing it's undoubtedly harder than or holds the same hardness that the cichlid substrate does. That's probably why you're seeing no difference in the tank full of wood and regular Eco. Not to mention there are the bad batches of Eco going around, and a temporary effect from good Eco as Imeridian mentioned. If super hard tap water is the case then you didn't even need the cichlid substrate to achieve more hardness (which is the important factor for hard water species over a specific pH, and vice versa for soft water fish).

Many things can alter pH without affecting hardness and the fish don't care. More important to match their natural hardness and ignore pH, it will follow hardness. Just remember that you're concerned with GH more than KH when you're matching a fish's natural hardness, lowering GH by dilution for soft water species will automatically lower KH (buffering capacity) and pH will follow. This is where people get hung up on what pH a species supposedly requires and most profiles don't clarify desired hardness unless it's somewhere like fishbase. If you mix it down to say 3dKH, you will probably be looking at a pH of around 7.2, GH will most likely be in the 'soft' category at that point, depending on the Ca and Mg levels etc in your tap. If GH is still too high at that point then you can mix further down, then if you choose to have some buffering capacity present you can add a bit of baking soda to bring KH up but the water will still be considered soft due to the low GH target, just be aware that bumping the KH will bump the pH, but GH is what you should be concerned with, not pH. Too many people use store bought snake oils or some source of acid in their discus tanks etc and don't even realize that their water is still hard because they never test GH, they only concentrate on pH and probably don't even know what their KH is either.

I agree an RO mix is your best bet to maintain an easy, constant, steady target. A $60-100 4 to 6 stage RO unit from ebay will get the job done and is cost effective over the long haul, especially if the tank is large or there are multiple tanks. Lugging bottles from the store every week gets old fast.

If you do use store water, make sure it has no minerals added. The refill stations out front usually list the filtration process on the front which often includes RO and maybe DI or UV, usually carbon block also. The commercial bottles will list whether there is any calcium, magnesium or potassium added, you don't want that.

[spinycheek]

I'll agree with the hardness thing. There is a natural reaction between KH, pH and CO2 that can get a little complex to calculate, but as long as the pH target is above 7, diluting with pure water will work fine. It's when you want an acidic pH that it becomes really necessary to add CO2. You probably won't be able to reach pH 7 without CO2 (unless there is no buffer at all), but if your KH is less than 3 you can get it down to 7.3 ish.

[Cook.MN]

Thanks for the responses all, and I have some updates...or lack there of sadly.

Since I posted I have been using peat moss in combination of using 1.5 gallons DI water on my weekly 10% water changes in hopes of slowly lowering the hardness of my water.

No change whatsoever in the water PH/Hardness. So it's still the same as my African Mbuna tank but with yellow/brown water tinge where as my Mbuna tank is sparkling clear.

I'm only doing 1.5 Gallons of DI weekly because I want to slowly lower the hardness of the water and I refuse to use any chemicals...the only chemical I use on any of my tanks (when not treating illness) is a dechlor.

Without investing in a CO2 system what are my options from there? I have thought about up'ing the amount of DI I use per weekly water change since this is a 55 gallon tank but I'm not looking to put something in my water then magically over night it changes.

[nate_mcnasty]

cook where do you live in MN ???

sorry this is off topic

[Cook.MN]

I'm in Mound...extremely hard water out here. My Mbuna love it tho.

[mpodolan]

My guess is that adding only 1.5 gallons of DI per week will never cause a change. I would guess more than that evaporates in that amount of time. when evaporation occurs, mostly pure H2O leaves, while the dissolved solids remain, which will tend to increase the hardness levels. You would need a lot more DI per week, IMHO

[Cook.MN]

Alright thanks, I was afraid of causing a rapid change in the water hardness that's why I was adding so little per weekly water change.

I thought between the peat moss, driftwood and DI that if I added a significant amount of DI it would cause too much of a change too quickly.

[Carissa]

I don't think adding peat will do anything to hardness....it just adds acids that may lower pH. You can get "pillows" that absorb hardness from the water....not sure how well they work or if they are a good idea, my water is 0 on both KH and GH so I don't have that problem. Why do you want to lower pH?

Edit: I looked up what information I could find, and evidently in addition to releasing humic acids (that lower pH) it can (depending on the source) also have the ability to do ion exchange and trap Ca and Mg ions by releasing a hydrogen ion. However, this would only affect GH, not KH, if this is correct information, as KH is a measure of carbonates, not calcium and magnesium. Removing Ca and Mg has no effect on pH.