• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up
  • You can now follow UKAPS on Instagram.

Anyone used the JBL SiO2 test?

orxe87

Member
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
Has anyone used the JBL SiO2 test kit and got sensible results?

I don't really like testing (either the philosophy or the practicality of it) preferring to see how things are doing with plants and fish as a better guide to water quality, but have a test kit just to be able to check if noticing something is out of balance. I was (very!) bored this evening so thought I'd test my tap water for SiO2, which is a test I've not used before. No diatoms left in my tank so I was expecting a low or zero result - it was just for fun(!) really. Surprisingly, it came back a deep, deep blue, which is nowhere along the yellow to dark green of the test chart for SiO2. I re-ran it three times thinking I'd made a mistake, but no, it's just simply not remotely in the correct colour spectrum.

Anyone know if that test is susceptible to other things in the water, or to contamination somehow? Not really a problem either way, just curious if I have a duff test kit...

Thanks!
 

dw1305

Expert
UKAPS Team
Joined
7 Apr 2008
Messages
11,942
Location
nr Bath
Hi all,
JBL SiO2 test ..........Surprisingly, it came back a deep, deep blue,
Probably a silly question, but might it be the low range phosphate test kit, rather than the silicate test kit? If it was it would account for the blue colour.

cheers Darrel
 

orxe87

Member
Thread starter
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
I wondered that, it's much closer. But three reagent bottles all mislabelled?

I was doing PO4 at the same time (which came back as zero), but it doesn't really match that chart's colours either, though much closer than the silicate chart. The SiO2 chart looks like it is heading towards blue at the end (it's kind of green-blue), so I guess it could be that I just have so much silicate that it is way off the scale... maybe I'll buy some RO water and see if I can find a silicate source to test the test kit!
 

sparkyweasel

Member
Joined
30 Jun 2011
Messages
1,891
maybe I'll buy some RO water and see if I can find a silicate source to test the test kit!
You could dilute your tapwater with RO water and see how the kit reacts to the lower level.
You could also get a tapwater report to see what level you should expect.
 

orxe87

Member
Thread starter
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
Good idea. An excuse to go visit the LFS too...

(I have the water report, doesn't show silicates :()
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,934
Location
Bracknell
Surprisingly, it came back a deep, deep blue, which is nowhere along the yellow to dark green of the test chart for SiO2. I re-ran it three times thinking I'd made a mistake, but no, it's just simply not remotely in the correct colour spectrum.

Hi @orxe87,

I have never used the JBL SiO2 test kit but the chart below clearly shows a deep blue when SiO2 is high:


JPC
 

orxe87

Member
Thread starter
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
It's a very different colour to anything on that chart - hopefully this shows it:
20210406_193557.jpg

There's still mostly green in the right-most circle - it really isn't blue at all.
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,934
Location
Bracknell
Hi @orxe87

On my PC monitor, the liquid sample in the vial has the best match with the right-most colour patch. In fact, it's a good match. But, it is best to set up the tubes as advised by JBL in the little booklet (and on the reverse side of the colour chart that JBL supply in the kit). That means that two vials are used, one of which is a "control". Take the caps off each of the vials and view from above.

If the reading is the highest value on the chart, it's important to dilute the tank water sample with RO or distilled water. Then multiply the resulting measurement by the dilution factor.

JPC
 

orxe87

Member
Thread starter
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
Hmm, not sure how else I can show how far off it is - it is really nowhere near a match, I promise! The >6 circle is a dark green, though with some blue. I do indeed use the method JBL specify, to the letter. I'm not colourblind, either :)
Dilution with RO is the next step.

This is definitely only for curiosity - no issue with diatoms, no reason to think that SiO2 is causing any negative effect in the tank.
 

Wookii

Member
Joined
13 Nov 2019
Messages
1,825
Location
Nottingham
It's a very different colour to anything on that chart - hopefully this shows it:View attachment 166514
There's still mostly green in the right-most circle - it really isn't blue at all.

Which patch are you referring to, the one on the far right (>6ppm)? If so, that is definitely a dark navy blue - very little if any green in it? I have the same JBL booklet here.

I suspect your test water simply has way more than 6ppm silicates (if you are correctly using 10ml of sample water?), it’s a fairly low level by all accounts so I’m not sure why the JBL kit has that as a ceiling. I read that 5-25mg is the common range, and up to 100mg occurs frequently.

As silicate levels have no bearing on anything in a planted tank, I’m not sure why JBL include it in their planted tank kit (other than the obvious profit motive).
 

orxe87

Member
Thread starter
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
Which patch are you referring to, the one on the far right (>6ppm)? If so, that is definitely a dark navy blue - very little if any green in it? I have the same JBL booklet here.
You're right - looking at it today under natural light it is more blue than green. I've just measured with a spectrophotometer to be sure - it has it as 'blackish blue', RGB 37 46 59, so very dark but also 25% more blue than green . I'm going to go measure the RGB of the kitchen LED lights next; hope it is that rather than my eyes... ;)

I'm still convinced the sample is a long, long way from that colour though. I'll repeat the test tonight and measure the sample colour too.
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,934
Location
Bracknell
Hmm, not sure how else I can show how far off it is - it is really nowhere near a match, I promise! The >6 circle is a dark green, though with some blue. I do indeed use the method JBL specify, to the letter. I'm not colourblind, either...
Hi @orxe87

One possibility for quantifying the colour on the JBL chart is to measure it. For this purpose, you could use an app such as Color Picker for Android. I've suggested this app before on UKAPS - mostly for checking the spectrum of aquarium lighting. Just point your phone camera at the JBL colour patch and it will quantify that colour in terms of RGB plus other colour measurement systems. Try to do this in daylight as other lighting will skew the results. Many years ago, I had need to get my eyes tested for critical colour matching in the job I was doing at the time. It turned out that my eyes/brain were not seeing blue/green/yellow correctly. It literally opened my eyes! The following is worth a look:


If I remember rightly, it turned out that I had slight blue-yellow colour blindness.

JPC
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,934
Location
Bracknell
I've just measured with a spectrophotometer to be sure...
Hi @orxe87

No sooner had I hit the 'Submit Reply' button a few minutes ago when I see you have access to a spectrophotometer. Please tell me more - either here in this thread or as a 'Conversation' if you prefer.

JPC
 

orxe87

Member
Thread starter
Joined
30 Jun 2020
Messages
28
Location
Shaftesbury
No sooner had I hit the 'Submit Reply' button a few minutes ago when I see you have access to a spectrophotometer. Please tell me more - either here in this thread or as a 'Conversation' if you prefer.
Ah, the joys of crossed posts - I nearly replied to your post before I realised you'd replied to your reply. Or something like that. I've sent a PM.

I'm annoyed at myself for discounting the effects of the kitchen LEDs on the colour patch, and also for not thinking of using the spectrophotometer earlier...
 

dw1305

Expert
UKAPS Team
Joined
7 Apr 2008
Messages
11,942
Location
nr Bath
Hi all,
Although not specifically a planted tank issue, it's surely related to the growth of diatoms. No?
I'm not sure you can directly relate the <"silicon (Si) content of the water directly with the growth of diatoms">. If you removed all the orthosilicic acid from the water column it would stop diatom growth, but it would have <"to be all of it">.

For me it is back to <"theoretically possible">, but all sorts of things eat diatoms, so we are somewhere near the best way to <"drink a glass of water">.

I don't noticeably have diatoms in any of my tanks, but I have <"Hornwort (Ceratophyllum demersum) in all the tanks">, which is also silicified, so I would be 99.9% sure that there is enough silicon to support diatom growth.

I'm much more interested in the <"probable compared to the possible">.
I've just measured with a spectrophotometer to be sure...........it has it as 'blackish blue', RGB 37 46 59, so very dark but also 25% more blue than green .
Try @jaypeecee's suggestion of dilution with RO water.

cheers Darrel
 
Last edited:

Wookii

Member
Joined
13 Nov 2019
Messages
1,825
Location
Nottingham
Hi @Wookii

Although not specifically a planted tank issue, it's surely related to the growth of diatoms. No?

JPC

Covered far better by Darrel than I ever can, but in short, not really no, as evidenced by the fact that hundreds of tanks on this forum alone function with surely a wide range of silicate levels, and no noticeable diatom growth.

Also as Darrel suggests the level of silicate required for diatoms to grow is far below what we could ever hope to remove.

Ergo, the level of silicates in the water is irrelevant in a planted tank.
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,934
Location
Bracknell
Hi @dw1305

It's rare that there is a simple cause -> effect relationship in lots of things, isn't it? I suspect that orthosilicic acid (H4SiO4) and other factors all play their part in the growth of diatoms whose hard frustule is comprised of SiO2. But, what is certain is that diatoms must obtain silicon (Si) from somewhere. Perhaps they obtain it from what they eat instead? If they can do this, that might - once and for all - eliminate tank water from the discussion?

JPC
 
Last edited:
Similar threads
Thread starter Title Forum Replies Date
LukeScapewalker JBL ProAquaTest Lab Water Chemistry 3
nigel bentley JBL Water test kit Water Chemistry 19

Similar threads

Top