Seachem Purigen Head Scratcher

[hypnogogia]

I anyone knows a way I can be more precise below "1" I would love to incorporate that in to my testing

Double the amount of your water sample. Then 1 drop = 0.5KH, although colour change may be difficult to see.

 

[Musicmanryann]

How confident are we in these PH measurements? Im sorry if I missed it (I have the attention span and memory capacity of a goldfish with alzheimers..) but what measuring device are you using, details?
KH and PH is not my best field but I think @dw1305 usually cautions about trying to measure PH in 0 KH water.

... and this one! (yes, you need lab grade equipment to measure pH reliably very near 0 KH).

Cheers,
Michael

Hi all,

It is a bit of a strange one, but yes @Hufsa is correct, pH becomes more and more unstable as you move towards pure H2O.

I don't tend to worry too much about pH, it isn't that it isn't biologically incredibly important (it is), but because <"measuring it accurately is quite problematic"> and it can only be interpreted if you have some measurement of the <"carbonate content (dKH) of the water">. I actually use the <"Snail Shell Index"> as my pH proxy.

I'll be honest, nearly all the things that you'll read about <"pH stability and buffering are wrong">

The "problem" is really with the pH scale, which is both a ratio <"and a log10 scale">.

At pH7 you have an equivalent activity of both <"proton donors (acids) and proton acceptors (bases)">, but pH doesn't tell us anything about amounts, just that our "scales" are balanced.

To <"use an analogy">, it could be a grain of sugar in either balance pan, or it could be a sugar cube or a bag of sugar. As long as both scales have the same mass of "sugar" our pH remains at pH7.

cheers Darrel

Thanks all for this perspective. I guess I am more than a little confused? Getting back to why I am measuring pH in the first place as I am monitoring the pH drop from CO2 as I continue to get it "locked in" as per @Zeus' methodology. It was observed that my drop checker might be a little yellow a few days before my livestock arrived, so I was slowly making adjustments to dial it down. My CO2 ran that morning, and I knew I needed to drip acclimate the shrimp for several hours anyway. So I turned the CO2 off early and ran my aerator to quickly dissipate a good amount of CO2 whilst the shrimp were drip acclimating, monitoring the dissipation with my ph meter. Again, my main concerns here were primarily excess CO2 causing increased stress, and secondarily I am worried about acidic water dissolving the snail shells. Also, it is my understanding shrimp can handle loads of different water, but they do not like sudden drastic changes. Well, the pH dropped 1.5 in a matter of twenty minutes. That bowl of water with the bag of purigen in it is reading 4.03 pH this morning. That number may be meaningless, but if I compare it to my tap water or RO water that have pH of 6.5 and 5.95, respectively, their relative difference doesn't seem meaningless to me. But I don't really know, is it meaningless or not? Also, it it is my understanding stability of water parameters in general is paramount to overall "success", or finding a balance with everything. So I guess I feel like I I was well intended here, but may have missed the mark in the application of my concern? I guess I don't really understand what I am supposed to be doing with pH then, if anything. I mean, am I supposed to measure pH and modify how I take care of my flora and fauna or not, lol? Just trying to learn where and when to focus my attention I guess, while wading through a lot of incomplete information, misinformation and/or noise, especially outside the walls of this forum.

Overall, everybody in the tank seems to be doing fine. I am likely making a mountain out of a molehill, as they say, which is admittedly an tendency of mine. I do agree with with @_Maq_ that taking some matrix out of the biomaster wouldn't hurt. I am going to open it up this evening after the photoperiod ends, give the matrix a good sniff and remove some. Working on starting a nano tank anyways so I'll give that guy a headstart on cycling with the martix from the 60P. I will report back my findings. Thanks everyone!

 

[Musicmanryann]

Double the amount of your water sample. Then 1 drop = 0.5KH, although colour change may be difficult to see.

OMG why didn't I think of that... Thank you!!

 

[hypnogogia]

If I could make a suggestion? I’d increase the KH slightly to say, 2 or 3. This serves two purposes - it’ll make you pH readings more reliable and your pH more stable. It’s easier that way as a beginner.

 

[LightingBamboozled]

Thanks for giving me a method to reliably measure flow! After a few failed attempts at gaining an accurate measure, I filled one liter from my filter outflow in between 6.5 and 7 seconds.

That's about 510-550 litres per hour which is pretty good for a stocked filter rated at 800. Unless something has changed significantly low flow cannot be the issue.

It was in the quoted portion of the OG post:

Current parameters are Zero NH3, Zero NO2, less than 10 NO3. pH 5.25. (GH 7, KH <1)

Sorry, missed them. No issues there.

Google image verified they are detritus worms. I had not observed them until the day the cloudy stuff came out of the filter after I agitated it. I saw them in the current of the water. Have seen a couple wriggling around the soil since. It very well could be they were in the water before this occurred, and I observed them because I was looking closer at the water because it was just polluted--they are tiny. I can't be certain though....

Detritus worms are not harmful, many fish will happily snack on them and they perform a similar job to snails like Malaysian Trumpet Snails in terms of feeding on leftovers in the substrate. They can be vacuumed out or left alone.

 

[MichaelJ]

If I could make a suggestion? I’d increase the KH slightly to say, 2 or 3. This serves two purposes - it’ll make you pH readings more reliable and your pH more stable. It’s easier that way as a beginner.

I strongly agree! Zero KH is really an anomaly, best entertained by the expertly skilled plant grower - not even sure if @Happi, @plantnoobdude et al. are doing that.

Cheers,
Michael

 

[plantnoobdude]

@plantnoobdude et al. are doing that.

I am... With soil. In my experience it works fine, and doesn't complicate stuff really. However, pH profiles can be a bit easier with some kh

 

[hypnogogia]

Zero KH is really an anomaly

Does it even occur in nature?

 

[_Maq_]

it's not a very natural thing and you really don't find zero KH in natural water ways

Within the limits 4.5 < pH < 8.3, part of CO2, which is always present, turns into HCO3-, which is alkalinity.

pH doesn't tell us anything about amounts, just that our "scales" are balanced.

To <"use an analogy">, it could be a grain of sugar in either balance pan, or it could be a sugar cube or a bag of sugar. As long as both scales have the same mass of "sugar" our pH remains at pH7.

You're wrong in this, Darrel, I'm afraid.

 

[MichaelJ]

Does it even occur in nature?

Not really. There always appears to be some CO3 - even in highly nutrient poor water.

Cheers,
Michael

 

[_Maq_]

I’d increase the KH slightly to say, 2 or 3.

2 or 3 °dKH ... increased slightly?
I can't afford even 1 °dKH because such a high alkalinity would push my pH well above 7.

 

[hypnogogia]

2 or 3 °dKH ... increased slightly?

Compared to some folk on here who grow great plants in very hard water yes, 2 or 3 is slightly and would still be classed as soft water. Given the OP injects CO2 as well, they should be fine.

 

[John q]

We don't need a lot of Alkalinity, whomever suggested this is... way off the mark. Suspect they are old time fish~ keepers, old habits die hard. Why do we need Kh???

 

[hypnogogia]

We don't need a lot of Alkalinity, whomever suggested this is... way off the mark. Suspect they are old time fish~ keepers, old habits die hard. Why do we need Kh???

I did. I know we don’t need it, but for a beginner it makes life easier to have some alkalinity as it increases stability when injecting CO2.

 

[MichaelJ]

We don't need a lot of Alkalinity, whomever suggested this is... way off the mark. Suspect they are old time fish~ keepers, old habits die hard. Why do we need Kh???

Sorry John, No one is talking about adding a lot of alkalinity… @hypnogogia and myself (running my tanks at ~0.5 KH) only suggested having above zero KH - like perhaps 2-3 KH as @hypnogogia suggested. Now, I never ever had issues keeping my pH in the sweet zone 6 to <7 pH with botanicals while keeping my KH at ~2.0 (or even slightly higher) so I’m not reading too much into @_Maq_ ’s comment above without more specifics about his “unique” circumstances… In any event we shouldn’t go overboard here and calling each other old timers (I know I’m old and so are my fish) for suggesting a bit of pH buffering capacity

Cheers,
Michael

 

[John q]

but for a beginner it makes life easier to have some alkalinity

Fair point. I could and probably should have chosen my words more carefully.

In any event we shouldn’t go overboard here and calling each other old timers

Lol, I'm an old fart... as above my word choice wasn't the best.

Regards the op and my comment about Kh.
Having some kh ~1 is plenty to keep the ph stable when injecting co2. I've no idea why your ph is dropping like it is but it might be wise to back the gas off a bit until you figure it out.

Also worth remembering that ada amazonia will drop your ph, that's what it does.

 

[dw1305]

Hi all,

You're wrong in this, Darrel, I'm afraid.

Why? I'm not a chemist so it is quite likely. I know theoretically that if you add a grain of "sugar" to either pan it tips, but in practice the greater weight acts as a buffer.

cheers Darrel

 

[hypnogogia]

I know I’m old

Me too! 😂

 

[hypnogogia]

You're wrong in this, Darrel, I'm afraid.

From my reading, I’d say he’s spot on.

The pH scale is logarithmic and inversely indicates the activity of hydrogen ions in the solution.

where [H+] is the equilibrium molar concentration (mol/L) of H+

 

[_Maq_]

but pH doesn't tell us anything about amounts, just that our "scales" are balanced.

From my reading, I’d say he’s spot on.

Maybe I've poorly understood. But pH always means the amount (activity) of hydrogen ions. Besides, [H+]*[OH-] is constant, which means that if we know [H+], we also know [OH-].