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Potassium deficiency?

I think it was Darrel who was saying not so long back that there is only certain places in the UK where magnesium comes out of the tap because of the Geology but in General most people in the UK will need to add it. Even in hard tap water areas in the UK the hardness isn't from magnesium so would still need some. Up north where I'm from the geology is mainly granite and slate so the water is extremely soft, same goes for Scotland but darn sarf with the shandy drinkers who have notoriously hard water the hardness is mainly made up from Gypsum which is more calcium related I guess. Hence the white cliffs of dover and gypsum being called plaster of Paris as I believe Paris is also built on it. Makes sense as France and England were joined at some point until a river turned into a channel after the ice age.

Don't know how this applies in other parts of the world. My water was extremely soft anyway until they decided to blend it with some underground water while work is being carried out and the TDS has doubled, much to my annoyance keeping softwater species fish.

I would say as long as there is no chlorosis in old leaves things should be fine on the Mag front.
 
Same would apply to Ireland as well as that was also a connected land mass with England. Hence the legend that St Patrick chased all the snakes out of Ireland but in reality the snakes couldn't get to Ireland, by the time England was warm enough for snakes the ice had melted and we had the Irish sea dividing the countries. Religion meets science again, just thought I'd share, prince of trivia me :D One day I'll remember something useful.
 
interesting discussion, i got this from Cambridgeshire water which indicates almost perfect levels of Mg and Ca in the mains water supply....would welcome any comments on this...

Capture.JPG
 
Well I only have 11mg/Ca, just over 1mg/l magnesium same for phosphates and nitrates and a conductivity of 109uS. You can see the difference in source waters and how they can affect plant nutrient uptake.

Calcium is the key is it competes with magnesium, potassium, and most of the heavy metals. In cases of hard water. More of these elements may be necessary to see improved health and growth. Especially magnesium as already stated. Calcium phospahtes precipitation could be an issue as well as iron phosphates meaning stronger chelates and possibles more iron dosing. You may need to add more trace elements too. More carbonate hardness higher ph also equals reduced micro nutrient availability.

Soft water comes with its own set of problems were micro element mixes become crucial. Too much of any one thing for any given tank can be detrimental or result in induced deficiencies. You may get away with dosing less macros and micros as AWB has alluded to because the calcium isn't there to compete or protect against toxicities. There's so much to consider and is the reason why EI isn't the silver bullet for all nutrient dosing and why many methods work for different mini ecosystems.
 
I dont think EI has ever claimed to be a Silver bullet to be honest. If you read the method correctly.
Full EI is a useful as a starting point for your fert dosing routine. You can then concentrate on your flow Co2 and maintence routine and forget about your ferts because they are in the non limiting range, more than most will ever need. Once you have this correct.Then you tailor the dosing to your own tank routine. So I totaly agree there is no one size fits all perfect routine.
Most problems seem to arise when people start to alter the ratios in the fert mix, forget the water change for one reason or another and jump straight on the ferts for the probable causes. When really the answers are something alot more simple.
And no I am not a EI fanboy or whatever I just use the best method that works for me. We would all like to be able to dose just the right amount of everything to suit our own tank. But in reality with the time and resources most of us have available to us this will never happen.
So we will all have some excess or another.
 
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EI may not claim to be the silver bullet but unfortunately and (unlike yourself in this instance) the vast majority of its users believe and claim it is.

There's too much contradiction on this forum. One minute EI is a starting point, an arbitrary figure, an idex. It should be tailored to suit your own tank. But then in the next breath all problems seem to arise when people alter the ratios in their mix or '99.9% of people have problems when they roll their own' or 'It's not supposed to be set in stone' then in the next sentence 'why are you inventing your own version of EI'? Etc etc. Confusing!

How can you avoid altering ratios if you can target EI using various different micro fertilisers? The target is 0.2ppm Fe but using what? A seachem product? CSM+B? Aquarium plant food trace mix? Millers microplex? They all have different ratios.
 
Well I only have 11mg/Ca, just over 1mg/l magnesium same for phosphates and nitrates and a conductivity of 109uS. You can see the difference in source waters and how they can affect plant nutrient uptake.

Calcium is the key is it competes with magnesium, potassium, and most of the heavy metals. In cases of hard water. More of these elements may be necessary to see improved health and growth. Especially magnesium as already stated. Calcium phospahtes precipitation could be an issue as well as iron phosphates meaning stronger chelates and possibles more iron dosing. You may need to add more trace elements too. More carbonate hardness higher ph also equals reduced micro nutrient availability.

Soft water comes with its own set of problems were micro element mixes become crucial. Too much of any one thing for any given tank can be detrimental or result in induced deficiencies. You may get away with dosing less macros and micros as AWB has alluded to because the calcium isn't there to compete or protect against toxicities. There's so much to consider and is the reason why EI isn't the silver bullet for all nutrient dosing and why many methods work for different mini ecosystems.

But if I remember correctly, Tom Barr lives in soft water areas most of the time, except Davis and Santa Barbara (USA). Now he is in SF with 0-1 dGH and dKH soft water.

The target is 0.2ppm Fe but using what? A seachem product? CSM+B? Aquarium plant food trace mix? Millers microplex? They all have different ratios.

Yeah, I see the problem here. The Seachem's would precipitate too easily in hard water while Cu level in Microplex would be over the roof (1200x higher than the Seachem's) to get the same 0.2 PPM of Fe.
 
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If I recall Tom has been rolling his own form of dosing regimen for a while. He wasn't following EI for micros at the time of this thread and he was throwing all kinds of chelated iron in.

http://www.plantedtank.net/forums/1...eters/853001-csm-b-toxicity-experiment-6.html

Tom most likely changes way more water than the average EI user so his nutritient concentration at any one time is difficult to extrapolate.

I like Tom but there is so much more to aquatic plant horticulture than flow and co2 distribution. We are so obsessed with co2 these days that it's become very difficult not to achieve the right levels for our tanks. If overdosing ferts work in every instance for every plant for every tank then we would all be talking about which plant placement looks best before we enter ourselves in to the next big aquascaping event rather than potassium deficiency.
 
Im no expert only really go on my personal experiances. Never having a problem with micros all I have ever done is reduce the dose amount I use. Ie I now dose 20ml daily not 25. But I also put the mg in the with the micro mix to.
But could the same not be said of any fert dosing routine not just EI?
Ask any question anywhere and you will more than likely get ten different answer's.
With regard to water changes if you run massively high light, high co2 to get the high growth rates reported I would expect the maintance will be higher too. So you will have to change more water.
The water changes are not just to reset the fert balance but also to remove the orgnic waste produced by the plants. So the higher the growth rate the more waste is produced, so the more water to change?.
 
I agree with all those comments. Tom most probably was or still does reset his tank at least twice a week. He's always advocated large frequent water changes. As too did Clive. But Clive's water hardness could not even be measured on the GH liquid test if I recall. His experience with dumping insane levels of fertilisers were meaningless to me. He was probably just precipitating most of his ferts and then pouring them down the sink. His plants were obviously feeding though.

Even EI dosing ratios will be manipulated by the ecosystem so its still different for everyone and that's why you get 10 different answers.

I've stopped using chelates. I mix my own micro solution. I may need to add more so that they stay in solution. I add large amounts of co2 mainly to reduce ph and make the traces more available. Still in experimental phase. I need to change more water myself. I can only gass off 20L at time which is only a third of my tank volume.

To be honest it doesn't look like potassium deficiency in the Original photos. More like they are being eaten. But as we know. Snails only eat dying leaves. May well have been issues long before the holes appear. Difficult to tell.
 
What about co2. I'm assuming when you say low tech you mean you have none or LC? What lights you got swinging above there and how long they on for? From what I gather your co2 will be coming from natural gas exchange with weekly changes maybe most is gassing off and your plant mass has hit a point where it's fancying a bit more carbon.

Sent from my STH100-2 using Tapatalk

Hi, Sorry for late reply I've been on holiday. Wifi rubbish lol.

Lights
Lighting is 2x 28 watt t5 juwel daylight tubes.
Period of lighting is 5 hours on a morning from 8am. Then off till 5pm when they come on for another 5 hours till 10pm.
The tank is in my front room, when the sun is out it gets around 45 mins real sunlight on an evening.

Carbon/co2
non, I wanted to avoid using pressurised co2. I chose "easy low light" plants in the hope that I could just get by low tech style.
I also want to avoid using gluteraldehyde as its not natural in my eyes.

--

So as a starting point, aquarium plant food has no stock of K2SO4. So I found this on amazon https://www.amazon.co.uk/500g-Potas...?ie=UTF8&qid=1499693853&sr=8-1&keywords=k2so4 same thing I assume.

Ill look to double water changes as a starting point and continue to dose EI at full dose. Once the ferts arrive Ill try adding a little as per zoo's advice.

Ill keep everyone posted.
 
But Clive's water hardness could not even be measured on the GH liquid test if I recall.

Yeah and the thought of expired GH test kit pops up every time when I come across this story. An expired GH test kit is just like that. I mean I don't doubt his water is very hard. But it should not be that hard. Just saying.
 
OK just wanted to say I managed to fix the problem. Reducing ferts didn't seem to do much. I used K2SO4. I added a pinch to the tank and also some into my macro mix.

Ive gone through that bottle of macro now and haven't added any k2so4 this time. I do have an algae problem, as in theres too much of it. It is under control and I've ordered dome hydrogen peroxide to help me out.
 
Calcium is the key is it competes with magnesium, potassium, and most of the heavy metals. In cases of hard water. More of these elements may be necessary to see improved health and growth. Especially magnesium as already stated. Calcium phospahtes precipitation could be an issue as well as iron phosphates meaning stronger chelates and possibles more iron dosing. You may need to add more trace elements too. More carbonate hardness higher ph also equals reduced micro nutrient availability.
Hello,
This statement is not true for aquatic plants. You, or your source for this information has extrapolated this from terrestrial plants. In aquatic plants, Ca and Mg+ do not compete, and neither does Ca compete with any metal. Therefore it is not necessary to dose extra anything, however, the good news is that you can dose extra everything without penalty.

Cheers,
 
Hello,
This statement is not true for aquatic plants. You, or your source for this information has extrapolated this from terrestrial plants. In aquatic plants, Ca and Mg+ do not compete, and neither does Ca compete with any metal. Therefore it is not necessary to dose extra anything, however, the good news is that you can dose extra everything without penalty.

Cheers,

Hi

Perhaps you are correct. This information has been extrapolated from terrestrial plants. I haven't seen anything of this related to aquatic plants specifically however, if for some reason the plant was to completely alter its evolutionary nutrient uptake mechanisms by being placed a foot underwater there are still penalties to consider with high something's with regards to fauna. Namely heavy metals. There are copious amounts of studies that show the protective effects of calcium on heavy metal toxicity in terms of microorganisms, fish, inverts etc. In hard water yes you may be able to does extra everything without fear of reprecussion however, instructing someone to do this in very soft water could be seen as boarderline irresponsible in my opinion.

Wouldn't it be great though if everybody could dose extra everything's without repercussions? That would mean that by grabbing a spraybar and some co2 everybody would have fantastic looking plants all of the time.

People have been attempting to dose extra everything for the past 10 years and have still not been able to recreate their most prized aquascaping inspirations. Why is this? I really do wish it was that simple or do I? Hobby might become a little less interesting.
 
Yes in walstads book she does confirm what soilwork is saying, more ca means less risk of metal toxicity.
 
Yes in walstads book she does confirm what soilwork is saying, more ca means less risk of metal toxicity.

She does. However alluding to Ceg4048's statement there is no information of toxicity towards aquatic plants in the book. Mainly it describes how soil, humic substances, dissolved organic compounds, Calcium and to a lesser extent magnesium protect fauna against such toxicities.

Depending on the substrate choice, source water, dosing method, micro element mix used and the frequency of water changes there may well be a chance that excessive levels of the heavy metals build up beyond the toxicity threshold of a certain species before the water change is able to reduce the concentration. It's the fact the we do not know what that threshold is for most of the species of creatures we keep in our tanks and the fact that we do not know the exact science of how these metals interact within the water column that makes it all the more important to be mindful of how much we dose.

I'm thinking of adding some crushed coral to my filter to raise the carbonate hardness and calcium levels of my tank water. With the ph nearing 6.0 it should dissolve readily.
 
Depending on the substrate choice, source water, dosing method, micro element mix used and the frequency of water changes there may well be a chance that excessive levels of the heavy metals build up beyond the toxicity threshold of a certain species before the water change is able to reduce the concentration. It's the fact the we do not know what that threshold is for most of the species of creatures we keep in our tanks and the fact that we do not know the exact science of how these metals interact within the water column that makes it all the more important to be mindful of how much we dose.
The level is so high you will never reach it. You never need to worry about metal toxicity.
What you do need to worry about is not having enough. This is more relevant to RO users, but even this is very easy to solve - just add some. The levels do not need to be high, but they can be high without any penalty whatsoever.

Cheers,
 
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