The Effect Of 0 Water Hardness.

So our tap water is pretty close to perfect. It measures 35 ppm and I'm pretty sure that's just the chlorine. There's no ammonia, no nitrites, no nitrates and the pH is pretty much 7.0 (slightly higher if we use it heated from the tank).

We have 2 tanks. A 55 and a 23. The 55 is older by a month or so. Two weeks ago I decided to only do a 25% WC on the 55 and do a normal 50% on the 23. The impact was noticeable. The pH climbed to around 7.4 (maybe higher?).



Move on a week, and I did (I really need to write the changes down...) at least 2 50% WC on both about 2-3 days apart.

And... what's that? 6.8 on the 55? Just from water changes. :|



While in the 23, where I've stuck to 50% changes almost since we got it (at least once a week). 6.6?




To me, this clearly shows how much of an effect 0 KH has on the pH of a tank. Definite consideration for buffers to stabilise that KH and thus pH over time...

-G

 

Oh, here's a photo of the hot (behind) and cold water pH tests.

 

whoa! that's incredible. @NavyChief20 have you seen this?!

 

G'day!

@Jenoli42 Im convinced you dont actually sleep LOL. KH and GH have an INCREDIBLE effect on water chemistry. One thing that you just demonstrated it temperature effect on pH.

It can have a huge impact due to various things, one of which is gasses coming out of solution. No water is perfect (other than the water that i make onboard my submarines), what i mean by perfect is that there will always be something in it. If you do a water change with warm water and say you notice your fish acting off abit it could be due to warming up or gasses out of solution leading to a momentary pH change. One way to mitigate that effect is proper fluid mixing as i have talked about in the past.

I know not everyone is an engineer and i dont expect everyone to know some of this stuff as it just isnt talked about in the hobby. If you think about your aquarium as a pool think about what goes into pool maintenance. You have to maintain that pump running for flow within the pool. Same as a tank, proper fluid mixing (chemical mixing) will maintain your water parameters much more stable.

Side note, I know @Jenoli42 runs some buffering additive (shells) in her tank @Brannor are you doing this too or rather are you now?


if you want to see something really impressive, fill two glasses of water, one with your tank water and the other with hot water. put 2-3 drops of food coloring in each and watch the dispersion.

 

I bought the Alkaline and Acid buffers (after speaking to @Jenoli42) a while ago but was first wanting to see the impact of smaller vs larger changes.

I have gotten my measurements from the Seachem forums and will be starting the buffering from after the next WC.

-G

 

3 days later.

 

So I left the tap water standing indoors for 24 hours to see the difference and here it is. Does that mean my tap water is actually closer to 7.6 than previously thought?

 

That's your water after 24 hour hold? When you do a hold or let it sit, water is going to off gas and any gasses that are in solution will tend to leave the volume. In some cases like co2 this means you could potentially have pH move to a lower level. You will also off gas cl and to a certain extent o2.

 

Yes, that's correct. 24 hours in a container on the counter allowing for off gassing. What do you think the pH is at from that photo? I know the hardness is 0 (or very close to), so will plan to buffer this evening.

My understanding from the guys at Seachem is that to reach a dKH of 4 and pH of 7.0, I should aim for 26.9g of Alkaline Buffer and roughly 13.45g of Acid Buffer. (55G tank).

-G

 

I use a digital pH meter instead of the api kit just cause I'm pretty much a nerd by trade. I would say you are a 7.5-7.6 which is impressive with zero hardness. Is there a reason you are trying to go to neutral?

 

 

I trust hanna instruments. They are well priced and sturdy. We use them for various water testing on the submarine as well.

 

First part. I've thought of getting a digital one for this. May well do so now that you mention it. Have a TDS one already.
From everything I read - and it's all confusing half the time - for the fish I have I should be aiming for 7.0. But I'd be happy with something that stays stable and the fish are ok in. So if that's higher (7.4 ish) and they're ok, and it stays there after water changes, then I believe that should be fine.

-G

 

Yeah there's pH levels you want to stay away from but realistically a stable pH is more what you want to shoot for.

 

Thanks. Will take a reading in the morning (API...) and see about raising the KH at that PH over the coming days/weeks.

-G

 

Here is the reading I just took. KH from 1 drop to 5 and then the pH reading. I've never actually seen a blue KH reading before.
Is that pH 8.0? Or 7.6? Can't wait for the digital one to get here... 8 seems scarily high considering the buffers I added should have pushed it towards 7.0. :|