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Can zinc be a problem?

x7 pumps = 10ml so one pump = 10/7ml

A percent is 10,000 parts per million. In order to express the results as a percent, divide the nutrient content (which is expressed in ppm) by 10,000. For example, if the reported value for P2O5 is 2,690 ppm, the calculation to convert to percentwould be: 2,690 ppm ÷ 10,000 = 0.269%

"parts per million" and it also can be expressed as milligrams per liter (mg/L)

one pump per 5 litres -so for 50 litre tank 10 pumps

so if my maths is correct from the values on the label

upload_2019-5-28_22-2-2.png


upload_2019-5-28_21-59-5.png


Fell free to correct me if I am wrong ;):thumbup:
 
Here's a comprehensive article on trace heavy element interactions, slightly specific that it's on Aridopsis root shoot interactions and induced Fe deficiency symptoms, quite interesting reading, it was published in July 2017 so it's fairly new. Highly detailed even looks at Fe EDTA and EDDHA chelates and also Fe foliar feeding application which reversed root fed induced Fe deficiency symptoms.

Heavy Metals Induce Iron Deficiency Responses at Different Hierarchic and Regulatory Levels

Worth a read.

:)
 
x7 pumps = 10ml so one pump = 10/7ml

A percent is 10,000 parts per million. In order to express the results as a percent, divide the nutrient content (which is expressed in ppm) by 10,000. For example, if the reported value for P2O5 is 2,690 ppm, the calculation to convert to percentwould be: 2,690 ppm ÷ 10,000 = 0.269%

"parts per million" and it also can be expressed as milligrams per liter (mg/L)

one pump per 5 litres -so for 50 litre tank 10 pumps

so if my maths is correct from the values on the label

View attachment 124638

View attachment 124637

Fell free to correct me if I am wrong ;):thumbup:

I wouldn't know where to start correcting!

The NPK values are interesting, I've run close to these ratios and quantities during my little trials. Same for Mg but wasn't getting the slight improvements I've seen from the Floragrow, so this must still be something to do with micro.

Also noticed the dark vein look the leaves used to have with the APF are disappearing while using the floragrow. With this vein problem specifically I've tried everything else, from K to Mg and nothing alleviated it.

Worth noting is that when using the APF with full tap water I was getting good growth, but only certain times of the year. Winter was better than summer for some reason. I initially thought temperature increases might have played a role but now I'm not so sure. There's something in the tap that's good that isn't in my reconstituted water. But what? My WQ report doesn't list cobalt (nor zinc for that matter) - there has to be some though, right?

I read that cobalt has only recently been recognised as a "Potentially" essential nutrient in legumes for nitrogen fixation. Again another interesting observation I made is that all my plants exhibit acute N deficiency. Those pale yellow old leaves, stunting on new rotala growth and the often huge build up of N by the end of the week.

So - saying all that, how would I best get some cobalt into the tank to experiment? I figure I'll give CSM+B a go for a few weeks and see what happens. If things start to go downhill then I'm willing to supplement Co and see if this is perhaps what I am missing?

Thanks for your efforts Zeus - much appreciated.

Thanks all, as always.

Just one more thing - would the trace mixes that don't specifically have Co contain sufficient levels as impurities?
 
From what I have read is that Fe and Mn will mop up Cobalt by forming complexes, so if Cobalt isn't dosed then it will deplete further chemically in addition to the biological depletion I mentioned above.

I'm not dosing Cobalt at all, I have the (II) Chloride Hexahydrate salt to hand but haven't added it to my trace mix after discussion over on the BarrReport in the Custom Micro Mix thread. I'm running about 3 weeks between water changes (remineralised RO/DI) longer than this and I get leaf curling, same daily dose of custom trace (11 months on this regime, where before it was an almost identical mix using Seachem Comp and Trace which has Co as an ingredient).

One of the Buce is starting to show this deficiency (centre of pic, one long rhizome with a couple of side branches).

image.jpeg


This may or may not be Cobalt deficiency, the variety of Buce is Theia Blue. I am unsure if Buce can eat 20ppm N in three weeks (front loaded Macro) as I always see a reading for it on the test strips (could be interference).

Any tissue destruction you can see on the Cherry Red on the left (and single hole on a leaf of the deficient Theia) is due to adding some sand substrate that turned out to have a calcium carbonate source in it making my GH and KH more than double (from 8 to around 20+) over the week due to added CO₂ and having a non-buffering substrate. You can also see some melt on the Java fern at the bottom.

Depending on how pure the base salts are Co could be an impurity, no way to tell unless the base salt has been measured for contaminants in the manufacturing process and has it listed on the product specifications.

Darrel suggested Silica Gel on the previous page for a source of Co, no idea on the mg/L Co it would provide but you could work out a ballpark figure for it, I saw it as a potential source of Co when looking for sources before I found the pure hexahydrated form on eBay that I still haven't used but now see the potential to add it (until BBA starts growing again).
 
If you go to get some Co, let me know and I'll split the cost with you. I picked up some boric acid and zinc sulfate in case you need some.

I've since also received the CSM+B, mixed it up and it's auto dosing daily 3 hours after macro. Values below (in ppm)

Code:
B        0.003430322
Cu        0.000385911
dGH        0.005015168
Fe        0.028
Mg        0.006003063
Mn        0.008018377
Mo        0.000214395
Zn        0.001586524

Macro:

Daily 1ppm NO3, 0.1ppm PO4 0.68 K

Water mixed up to this recipe:

Ca 40
Mg 8.4
Cl 35
S 16

GH 7.3
KH 3

Photos from today:
https://drive.google.com/open?id=1SgV8M6oCSPivlZa7rIQqEh4xVYrvIPP_

Going to run this for a week and see what happens.
 
I ran the week as intended and had NO3 lingering again toward the end so dumped in 20ppm of K as K2SO4 and today the NO3 and PO4 is completely undetectable?! I can't believe that I might be deficient in K but to test the theory I'll be starting the new week with the same water recipe except I will add 20ppm of K directly to the tank after WC then up the macro dose to 4ppm NO3 - 0.4ppm PO4 - 2.72ppm K daily.

I'm keeping the micro dose the same with the CSM+B - 0.03 Fe as proxy, a day.

Interesting to note that algae is and has been non existent. Just a very small skin of GDA on the front glass. I've not suffered BBA, staghorn, brown, cyano etc for a very long time.
 
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Hi all,
I ran the week as intended and had NO3 lingering again toward the end so dumped in 20ppm of K as K2SO4 and today the NO3 and PO4 is completely undetectable?!
It could be the tank was potassium (K) deficient. Because nearly all potassium compounds are soluble any potassium present in the tank will be as plant available K+ ions. Once K+ was non limiting the plants could take up the "spare" NO3- and PO4--- ions

The other option is back to the difficulties of keeping PO4--- ions in solution (and of measuring NO3- ions), your PO4--- may have precipitated out as calcium phosphate complexes etc. I'm always wary of putting too much credence to NO3- measurements, even in the lab. using an ion selective electrode.

That is why I like the <"Duckweed Index"> (from <"earlier in the thread">) it does away with the need to accurately measure nitrogen. If you have dark green, healthy "Duckweed" (Amazon Frogbit (Limnobium leavigatum)) you have plenty of nitrogen.

cheers Darrel
 
Hi all,It could be the tank was potassium (K) deficient. Because nearly all potassium compounds are soluble any potassium present in the tank will be as plant available K+ ions. Once K+ was non limiting the plants could take up the "spare" NO3- and PO4--- ions

The other option is back to the difficulties of keeping PO4--- ions in solution (and of measuring NO3- ions), your PO4--- may have precipitated out as calcium phosphate complexes etc. I'm always wary of putting too much credence to NO3- measurements, even in the lab. using an ion selective electrode.

That is why I like the <"Duckweed Index"> (from <"earlier in the thread">) it does away with the need to accurately measure nitrogen. If you have dark green, healthy "Duckweed" (Amazon Frogbit (Limnobium leavigatum)) you have plenty of nitrogen.

cheers Darrel

My tank isn't really equipped for duck weed because of the skimmer and above average flow. I only use the NO3 test kits to see if there is no NO3, not to see if there is any. If that makes sense? Not perfect by any means but it gives me a rough idea.
 
Hi all,
I only use the NO3 test kits to see if there is no NO3, not to see if there is any. If that make sense?
It does, but I'd still be wary of basing too much credence on the NO3 tests.
My tank isn't really equipped for duck weed because of the skimmer and above average flow
Point taken.

cheers Darrel
 
Hi all,
Sorry if I came across a bit harsh - I suppose I could fence off a little bit to test.
No you are good, I'm just a floating plant obsessive. It is only a matter of time before I start knocking on random doors and asking people if they've heard the "good news" about Amazon Frogbit.

cheers Darrel
 
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I also run quite fast surface flow, unsuitable for free floaters but Crypt Balansae grows extremely well when it hits the surface draping across it with access to atmospheric CO₂.

My balansae used to be incredible! A rich orange/brown colour. It used to get out of control quickly so got rid.

As for the tank now, I've stopped dosing NO3 and upped trace to 0.1ppm Fe every other day with 1.3ppm PO4 and 5ppm K going in in between.

Also turned one strip of lights off to slow things down a bit.

Something to note is the dark green veins on pale green leaves (both new and old) have disappeared almost (most prominent on the wisteria). If the charts were anything to go by that would indicate Mg but this looked like a stress induced veination since I know exactly how much Mg there is in there and it couldn't possibly be that.

I'm going to continue with no NO3 dosing and see where it takes me. Then when/if the need arises I am literally going to start at 1/2ppm a day from Urea.

Is there a certain calculator that people use?
 
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I use Rotala Buttefly mainly for ease of use but if something isn't listed I use the Molar Mass and Elemental Composition calculator over on WebQC.org Chemical Portal, it takes a bit of getting used to the format and the calculations needed to translate the results for dosing have to be worked out by hand, not an easy task for the mathematically challenged (sticks hand up!).
 
Cheers X3NiTH!

So here's the deal - things are..... actually looking up!

I stuck with the low fert regime and things were going downhill.

Stellatus was shedding lower leaves badly and new growth chlorotic.

Repens old leaves looking like a tortoise shell pattern.

Wisteria was dark veins pale green leaves, both new and old.

R. rotundifolia had a dark green spine on mature leaves with yellow edges - they were also very narrow.

Sunset was stalled in growth... what growth there was, was yellow and chlorotic. New leaves were also cupped around the edge like a teacup. Old leaves pale/light green with no uniform size to each other.

The cardamine was stunted - I know my neon green tetras and amanos eat new leaves in the night (I caught them both) so I disregard this one.

Green velvet is hanging in there - throws new leaves now and then but they deteriorate. No biggie, I knew it wasn't going to like what I was doing in the tank.

Baby tears have perked up. This is always a promising sign for me. A great indicator plant with a quick response. Keeping my eye on this one.

Crypts are literally solid through all this. I loaded a couple root tabs deep in just for them few months ago and they are clearly benefiting.

I ditched the low dosing and went back to more or less full EI and was still having the above symptoms though some alleviation was observed. I've not been auto dosing and current dosing is a bit of a mess BUT I changed something else and saw an almost instant reaction.

THE LIGHT!

Not the brightness but...... the spectrum. I was remembering back to when I grew this.

https://drive.google.com/open?id=0B-S3FwfLrLBsQjNPRnpkcUJXS1U

I was scraping my mind for what was different with the light? I basically took the blues out. Not sure why, I think I got the idea in my head that it didn't really matter to lose the blues and keep the 6500k LEDs with a couple of reds for aesthetics. Well clearly that was a mistake for whatever reason! I mean look at the plants in the photo above with the monte carlo carpet - they all look a damn sight better than the pictures I showed before, right?

SO - I now have:

20 x 6500k daylight LEDs
6 x Royal Blue 440-450nm
2 x Bright Red 620-630nm

I'm not chuffed with the colour rendition but I think I might be able to mess around with that later as the blue/whites are on one dimmer with the red/whites on another. Plus I have the RGBW strips if I fancy a bit more of a purply/pink look later in the day.

Either way it seems heavier to the blue spectrum than the red is good.Maybe if I went and took the reds out and left the blues, I might have different problems? I'm having visions of being able to in a way "veg" the tank with high blue spectrum and "flower" or "colour" the plants pink by upping the reds? I've had perfectly pink rotala rotundifolia before, years and years ago though and again I'm pretty sure the last time I saw that was when I changed tanks and mucked about with the lights again.

Anyway, check the pics out in my Drive below.

https://drive.google.com/open?id=1qjv3I5N85Itl4x6ZsbqKnSM-AuRfhHYv

Those are the plants today after running the below setup for a few days. VAST improvement I'd say!

https://drive.google.com/open?id=10-zJO3qmc4Prr13a9IiPfkPDgAoKyk6J

Plan now is to do a 50% water change with the Colonel's (X3NiTH) recipe >_< and start EI again tomorrow while blasting the tank with light, CO2 and some extra flowwwww.

I'll keep you posted
 
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I dropped my Micro dose to 4 in 7 and I'm now over 4 weeks between the last water change (7in7 dosing I could only get to about 3 to 4 weeks before I was getting toxicity/deficiency symptoms), Buce are still growing, leaf production has slowed considerably in the last week though (a small bunch of Java fern and a couple of Anubias Longifloria were added about 6 weeks ago and the Balansae has increased in size considerably so that is providing more shade over the plants), some Theia varieties still exhibit some leaf curl, the less crenulated the leaf is the more the affected leaf rolls around the edges (seems to be no preference for upcurling or downcurling) I tested the KH and it has dropped from 7.8 down to around 4 (Inert substrate so the plants and filter fauna ate it up). I have been feeding more granular food to the fish rather than bloodworm so it's probably supplying a trickle dose of phosphate also (haven't tested for it) so growth hasn't slowed to zero. Tank and water look pristine, zero algae observable in the tank all leaves are free from it (there is GDA and GSA on the tanks cover glass, but in the tank BBA was my bugbear). I'm thinking of adding some potassium bicarbonate to my carbon dose to trickle feed the tank some KH to keep the levels up.

:)
 
This is an old thread, but I've had issues for years with some plants, and could never seem to get things right. I had all the tools, followed all the journals, mixed my own traces, focused on CO2, flow and cleanliness, and so forth. Recently I made a trace mix without zinc and things have never been better. I must have some in tap water and some residual from some O+ tabs. I also noticed when I tried Flourish Trace, at recommended levels, that plants reacted terribly, overnight. Now, AR Mini is growing with flat leaves, plants appear more full, Ludwigia Glandulosa looks good and is growing well. I realize this is just one anecdotal report, but I've been in this game for a long time and have done my homework, trying like mad to find out why certain plants would not grow well - ones that others do with ease.
 
Hi all,
Welcome to UKAPS.
I must have some in tap water
Zinc (Zn) is a common contaminant of tap water. It isn't particularly toxic to people, so it isn't a major concern for water companies. <"https://www.dwqr.scot/media/iagfid5g/pws-parameter-information-zinc.pdf">.
...... The USEPA sets a secondary maximum contaminant level (SMCL) for zinc of 5.0mg/l.
If you live in a fairly dry area of the USA (or an ex-industrial one) then you have more chance again. The UK adds sodium hydroxide (NaOH) and phosphate (PO4---) to our tap water, to raise the pH and precipitate out any zinc, copper (Cu) & lead (Pb) ions. A lot of zinc contamination in surface water in the UK is from galvanised "corrugated iron", fence wire, brake and tyre (tire) wear etc. <"Pollutant information - NAEI, UK">

We used to have a RTZ zinc smelter in Avonmouth (just N. of Bristol) <"National Smelting Company - Wikipedia"> and that has contaminated quite a wide area. Same with the <"landfill leachate"> we've analysed, heavily contaminated with zinc, probably mainly from the tyres used to line the waste cells.

cheers Darrel
 
I've read through this old thread and here are some of my thoughts:
You might expect 12 times the concentration of hydrogen and hydroxide anions as your pH swings, meaning that many trace metals could quite literally break their existing hydrogen bonding (in the substrate - not likely in your case)
I'm not sure whether pH moves that markedly in the sediment as a result of CO2 on/off injection. Firstly, the diffusion between sediment and water column is rather slow. Secondly, in the sediment, pH is mainly influenced by factors in situ, primarily by microbial activity, and also by plants' roots. Thirdly, Ponnamperuma has studied pH of submerged (flooded) soils and demonstrated that they tend to approximate neutral pH, no matter if water column is acidic or basic.
I think activated carbon is one of the best suggestions I have ever read for dealing with trace metal toxicity
Again, I'm not sure. Couple of years ago I've studied this question quite extensively. Adsorption of transition metals on AC is indeed possible. Yet, AFAIK water processing plants do not use AC for that purpose, it's not sufficiently effective. Aluminum and iron (hydr)oxides are stronger adsorbents for these metals (albeit together with phosphates and silicates).
Of course, treated (coated) activated carbon may be a wonderful adsorbent for selected metals (or other species). The problem is price, and for us hobbyists - availability.
It is strange that you are having this problem on an inert substrate.
I think a sandy substrate is inert only in the beginning, a few weeks, perhaps. Dead roots, lysed microbes, their biofilms, plus dead organic matter settling from the water column quickly form a significant mass of detritus. Detritus is known to be quite strong adsorbent for various species. The more so if in interaction with iron oxides and clays.
My experiments suggest that one year old sandy substrate is a significant reservoir of all nutrients. (I've attempted to document signs of complete lack of selected nutrients. I've made a 100 % WC and re-mineralized with the nutrient in question completely missing. I've waited a month, two, three, ... and no signs of deficiency appeared, while the plants kept on growing. Since then, I do not underestimate detritus as a source of nutrients.)
Plants have a cobalt (Co) requirement
Have they?
Just don't add the trace element solution on a regular basis, wait for the start of deficiency symptoms.
Microelement toxicity probably happens more often than we admit. It's quite difficult to diagnose.
I think that "complete micro-fertilizers" are very dangerous. Of all micros, iron is in want most often, by far. That's thanks to specific features of iron. Unfortunately, when signs of iron deficiency appear, many hobbyists dose complete micros! Micros other than iron then accumulate.
Additionally, micros adsorb in the sediment. Therefore, no water change will dilute them. Then, if disturbed in some way - physico-chemical changes, but very likely re-planting or re-arranging hardware is enough - they may release in the water column in toxic amounts.

I think an interesting way of dosing micros is "fertilizing" with food-grade Chlorella or Spirulina powders. Sadly, both of them lack boron (boron is essential only for higher plants), but Spirulina definitely contains cobalt (it's an essential element for cyanobacteria). I've experimented with these fertilizers briefly, and it works. Plants grew for three months without any additional micros dosing (RO+DI water, no fish feeding etc.). The drawback was that I've got suspicion that they supported algae. More tests would be necessary to assess this question with more clarity.

In general, I'm of the opinion that nutrient deficiencies occur more often in more abundantly fertilized/mineralized tanks. I think the reason is that nutrients are not absolutely missing but their availability is hindered by high concentrations of other nutrients. Most of the time, I work with soft water and lean dosing, and I rarely observe signs of nutrient deficiencies.
 
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