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pH profile during start-up

Again, the DC is absolutely useless for this type of investigation, however, as I mentioned, if you have a DC, then presumably you also have the DC reagent which is just a pH test kit. That satisfies option 2 above.


Cheers,
 
Well, you\ll be diluting the tank water with water that has only atmospheric CO2 dissolved in it which will tend to be an underestimate, by how much I have no idea. Yellow really doesn't mean too much with this, thinking on it, because pH 6.0 is the lower limit of Bromothymol Blue's ability to measure pH. So it will go yellow at 6.0 but it cannot tell the difference between 6.0 and 5.0 and with 2 KH water you probably need to be closer to 5.0 than to 6.0.

You'll need to raise the KH of your water or go insane thinking about this stuff....surely you must have Arm & Hammer baking soda in the kitchen cabinet. If not, I'm sure it's on sale at Tesco....

Cheers,
 
Yeah, that's fine. Use your KH test kit to verify the KH.
In the long term it's better to use coral sand in the filter which will be high in Calcium Carbonate and will dissolve slowly.

The baking soda is a quick fix, but sodium is not really a nice thing for plants long term. Go with that for now, but think about other options such as oyster shell coral sand or Potassium Carbonate.

Add it slowly, over a few hours....

Cheers,
 
The only baking soda I could find at short notice (Dr Oetker!) also contains 22% corn starch and a mix of both Sodium Bicarbonate and Monosodium phosphate.

I think I'll wait until I can find some pure stuff or just buy some aquarium re-mineralisation salts like JBL Aquadur.
 
Here is the profile for today with increased KH so hopefully the pH meter readings are valid.

KH = 4

Time ----- pH
09:00 --- 6.43 CO2 ON
09:30 --- 6.10
10:00 --- 5.93
10:30 --- 5.83
11:00 --- 5.78 increased CO2
11:30 --- 5.66
12:00 --- 5.58 Lights ON
12:30 --- 5.52
13:00 --- 5.48
13:30 --- 5.43
14:00 --- 5.44
14:30 --- 5.45
15:00 --- 5.45
15:30 --- 5.45
16:00 --- 5.45 CO2 OFF
16:30 ---
17:00 --- Lights OFF
17:30 ---
18:00 --- 5.73

So the pH drop is still too small and too slow. Tomorrow I'll crank up the CO2 yet again, although I won't have time to do another profile for some time.

Many of the plants have melted so much that I doubt they are salvageable. The only ones growing are the mini Java fern and Marsilea crenata (the old leaves have melted but have been replaced with new stems).

I think I might have to go back to using an in-line atomiser or a maybe a bazooka type atomiser for finer bubbles.

I'm using this diffuser and I really like it but the bubbles are perhaps too big (I've only used in-line atomisers before). It seems that many bubbles escape to the surface even though the diffuser is right next to the filter intake.

I have a feeling that this tank is using more CO2 than my other one which is twice the volume.

P
 
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Doesn't the 1-2 unit pH drop for an ideal pH profile assume that all CO2 is degassed overnight?

I angled the spraybar upward last night to create more surface disturbance. When I got up at 7:00 the pH was 6.90 rather than the 6.43 of the previous morning.

I put the spraybar back to the normal position and by 17:30 when I got home, the pH was the same as the equivalent time yesterday: 5.6.

Maybe there is a smidgen of hope that I have got sufficient CO2 and this meltfest may be averted?!

P
 
Doesn't the 1-2 unit pH drop for an ideal pH profile assume that all CO2 is degassed overnight?
No, all of that is taken into account. It's just a rule of thumb.

I angled the spraybar upward last night to create more surface disturbance.
Don't do that.

When I got up at 7:00 the pH was 6.90 rather than the 6.43 of the previous morning.
That's why.

I put the spraybar back to the normal position and by 17:30 when I got home, the pH was the same as the equivalent time yesterday: 5.6.
Maybe there is a smidgen of hope that I have got sufficient CO2 and this meltfest may be averted?!
Good. Just observe and make injection adjustment if you continue to see melting. You can also supplement with liquid carbon (assuming you don't have any sensitive plants).

Cheers,
 
Thanks Ceg. It's damn disheartening to see the plants melt away but I don't dare buy more plants for fear of wasting money. I think the Hemianthus glomeratus is 90% gone and the Crypts too. The Marsilea is fine and the 'Monte Carlo' is hanging on. I have tonnes of 'Monte Carlo' in my other tank which I could transplant over but I feel like that's cheating!
 
NO. Solving the riddle of your tank is never cheating. Saving money by using plants you have in abundance is NEVER cheating.

Do not think like this. That is what they teach you in The Matrix to turn Human Beings into a Cash Cows.

Cheers,
 
That is what they teach you in The Matrix to turn Human Beings into a Cash Cows.
I guess I should watch this film. Will it help me grow healthier aquatic plants?

JPC[DOUBLEPOST=1409004543][/DOUBLEPOST]
The Salifert one is very good.
Hi Sacha,

What makes the Salifert kit particularly good? Accuracy, ease of use, value for money?

JPC
 
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So we can use hobby-grade test kits to measure KH?
No. KH test kits do not actually measure KH. They measure alkalinity. For the purpose of this exercise however, the number that we get gives us an idea of what the pH drop should be (low, medium, high).

So, again, to clarify, for the 1,000,000th time, if you use hobby grade test kits to measure important things like Nitrogen, Phosphorous and Ferrous/Ferric compounds you will always have trouble because they are not capable of accurate or consistent measurements. DO NOT use test kits to tell you how much nutrition to add to the water column.

The test kits that measure innocuous things like pH/KH/GH are less ridiculous, can be outsmarted when necessary, but can still cause tremendous trouble if you attribute more importance to those parameters than you should, and if you do not understand the fundamental properties of those things being measured.

Have you paid attention to the difficulties experienced by the OP in this thread or have you simply been rooting for the test kit? How much trouble has he had just trying to outsmart his pH test kit and probes? Have you thought about how elaborate and absurd are his necessary procedures just to ensure useable pH data while all the time his plants are disintegrating? You think the OP is happy right now? You consider this to be a validation of test kit heroism? Sorry, but I consider it a national disgrace.

At the end of the day, it doesn't really matter what numbers his test kits report, because ONLY the survival or demise of his plants will indicate success or failure. The test kits can only ever verify the results observed in the tank. They can never determine or predict the results.

Test kit lovers blindly trust the numbers reported and constantly experience failure. Test kit haters find alternate means of working around the kit's inherent weaknesses.


The Salifert one is very good.
Dream on Copper Top.....mooo....

Cheers,
 
Am I right to assume that the crushed coral recommended is only for the purpose of increasing the KH so that pH measurements are faster and more accurate? Should it be removed once the pH profile is taken? Or just leave in the filter long term?
 
Condescending and patronising comments aside,

The Salifert test is a titration test kit, meaning it provides good resolution to an accuracy of 0.2.

As Clive mentioned, it measures alkalinity and then uses an algorithm to arrive at a "KH". The KH reading isnt 100% reliable. But it is the very best you can hope for from a hobby- grade test kit.
 
Condescending and patronising comments aside,

The Salifert test is a titration test kit, meaning it provides good resolution to an accuracy of 0.2.

As Clive mentioned, it measures alkalinity and then uses an algorithm to arrive at a "KH". The KH reading isnt 100% reliable. But it is the very best you can hope for from a hobby- grade test kit.
Hi Sacha,

I also understand that Red Sea make a good alkalinity test kit. Have you ever tried this one? I noticed that it is available from here:

http://www.marineaquatics.co.uk/shop/red-sea-kh/alkalintiy-pro-test-kit.html

There is a video review of Red Sea along with Salifert and Hanna KH testers on the net. If I find the link, I'll add it here.

JPC
 
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