Search results for query: duckweed index

Hi all, I'm not convinced, mainly because it is the mechanism that <"phosphate stripping"> uses at wastewater plants. Are you saying that the phosphate (PO4---) level is to low to precipitate out the iron (Fe+++) ions? or that the HCO3- and OH- ions will mop any ferric iron (Fe+++) ions...

...well, but they are expensive bits of kit. It was actually the <"issues with nitrate (NO3-) testing"> that initially led me to the <"Duckweed Index">. I'd agree with @jaypeecee, do whatever you feel happiest with. Personally I'm not going to go back to regular water testing, but if people...

...work, but I'm not sure it necessarily makes <"you a better aquarist">. That was really the reason for the development of the <"Duckweed Index">, it is a simple methodology and it hides all the <"interesting / scary bits"> under the bonnet. All you need to do is <"watch the plants">. It is...

@MrMarlow We are no way talking plants dying what we mean is (see @The Miniaturist in his post) the Duckweed Index tells us because floating plants have access to unlimited CO2 we can work out what they need ,fertiliser,to add if they show any deficiencys . If you have a soil substrate it's...

Ah, the duckweed index. I have quickly read over a thread on that somewhere. I shall read it a little more thoroughly this time. Thank you.

Have a look at the "duckweed index" on this forum (sorry, I don't know how to add a link). The basic idea is, because floating plants have access to the more abundant atmospheric CO2, the main deficiencies they can show are nutrient ones & they are likely to show symptoms before the submerged...

...it? Meanwhile the floating grass in the cube has grown interesting chubby stems. It almost looks tasty. And as you can see my Duckweed Index is contaminated with… duckweed. Will need some work to clean up. The cube needs work anyhow. After most algae have subsided it is unfortunately...

Hi all, That was the idea behind the <"Duckweed Index">, that the plants would <"maintain high quality water"> and that the only requirement for adding nutrients was to <"maintain some plant growth">. Because I want the plants to be able to respond to any <"increase in bioload">, I actually...

Hi @dw1305 Having never used the Duckweed Index to any meaningful extent, what are the implications for submersed plants as regards lighting intensity? Floating plants will obviously receive more light than submersed plants and floating plants receive the same spectrum as that being emitted by...

Hi all, What @John q says, either lack of light or lack of CO2. cheers Darrel

For me it would indicate that the issues aren't nutrient related, at least not lack of nutrients. I used this method when reducing my dosing and when a noticed issues with the frogbit I knew I'd reduced the fertiliser to much. Frogbits a good canary for "nutrient" deduction, it isn't starved...

Yes, I got that part wrong. Sorry. Hi @kayjo, I have not experienced this myself, but in my case I used it only in low-tech tanks with easy plants. I suppose it depends on what type of plants we are talking about, and if this a low- or high tech tank, what the state your tank is in etc.. If...

What does the "Duckweed index" indicate when the floating plans are thriving, but all the submerged plants still are unhealthy and dying?

...(Mg) and iron (Fe), and consists of a small slosh of <"very pale blue Miracle-Gro"> (when I think the tank needs it, based on the <"Duckweed Index">) for everything else. When I run out of "Miracle Gro" I've bought a kilo of <"Solufeed 2 : 1 : 4 mix">. When I start with the <"Solufeed">...

Hi Darrel, I might not be the only one being curious about what you are dosing so I thought I would ask. Do you target any specific ppm's with your fertilizers? what's your technique? :) Cheers, Michael

...it is a while before the plant grows new healthy leaves, even when that nutrient becomes non-limiting. I'm actually using a <"hybrid duckweed index"> at the moment, where I add iron (Fe) and magnesium (Mg) on a regular basis. The advantage that Lemna minor has, is that it has a very quick...

Very smart indeed - and he doesn't use very much (citation needed)... and its very, very livestock friendly!... super low conductivity with rain water... dare I call it lean - without the drama :lol: I am more or less using my "duckweed" (actually Frogbit, Pennyworth and Duckweed) to gauge the...

Yes, I encourage all low tech folks to give the Duckweed Index a try, all you need is some floaters and complete fertilizer. Add in a cheap TDS meter and you have pretty much all the information you need about your plants needs. It is like the opposite of EI, genius nonetheless. I'm pretty sure...

Well @dw1305 adds ferts when his duckweed isn't so green, Via his duckweed index and does a WC when his TDS goes above a certain level, he calls it 'a low carbon foot print approach' or was it 'lazy approach' - I think its a 'smart approach' ;)

You could write to the fertiliser manufacturers or you could use the Duckweed index.

...is nothing new and still he keeps going, he must have his reasons. I personally like the lean concept, it reminds me of @dw1305 's Duckweed Index. However, I believe all this talk about ratios and magic formulas to be mostly bs. And on top of that I have absolutely no interest in growing...

Hi all, A re branding, now that is an idea. The "problems" (purely in commercial terms) with the Duckweed / Frogbit Index are that: It <"works really well">. So once you have Frogbit in your tank <"your problems go away"> and you forget that they ever existed. You only have to buy the...

...you’ll ever need in setting up planted tanks. Even tap water with chlorine used to be aerated until it was gassed off. No one even has time for that anymore. Most folks used rain water to avoid even that hurdle 🤷🏻‍♂️ Duckweed index 😂 You could rebrand it frogbit index for fresh appeal Darrel.

Hi all, The problem is the one that @Happi mentioned, we are looking at ppb (10^-9) levels in terms of plant requirements and still relatively low levels <"in terms of plant toxicity">. You can get <"deficiencies of cobalt (Co)"> (or any of the other essential micro-nutrients for plant...

Which, in effect, is a version of ‘lean dosing made easy’ 👍 I wonder if, in a tank with high light, Co2 and ‘difficult’ stems, whether there would be any degree of separation between the point at which such plants perform well and the point at which the ‘canary floater’ starts to suffer. i.e do...

Hi all, That was the original rationale behind the <"Duckweed Index">, just <"add "enough"> when the plants begin to signs of distress. All the time the plants are healthy (and in some form of growth), just carry on with water changes etc., but <"don't add any fertiliser">. I used this...

...but I'm still not very good with fish and I don't see problems arising in a way a better fish-keeper would. The idea behind the <"Duckweed Index"> was a simple one, plants are good for water quality, so cut through all the technical detail and just give a mechanism to keep plants in active...

Hi all, That was one of the reasons I needed <"a floating plant"> for the <"Duckweed Index">, they always have access to at least <"400 ppm of aerial CO2">. They can't be grown emersed (or if they are they don't need to acclimate to being submerged) and they are, pre-adapted to <"incredibly...

Just start using ferts when you see any signs of deficiencies. Search on the forum for "duckweed index" - it's one of the best indicators for plant hungriness, moreover - with some of the training it will lead to the best richness in color of the red plants and you can control the green hue of...

Hi all, Yes, this actually comes up in one of @jameson_uk's threads, where he is trying to use the "Duckweed Index", but is hampered by <"red-green colour blindness">. My dad was red green colour blind and it made <"Raspberry picking interesting">. I don't. I don't actually <"try and...

Right lads thanks. Will pass the info on. Its kind of Ironic for TNC to call itself complete.

Hi all, If you look at the new leaves (like the one on the right of the plant, and the one left centre) they are really pale and almost translucent. I'm pretty sure that you also have a nutrient deficiency, and it is likely to be <"either iron (Fe) or manganese (Mn)">. This is <"iron...

Hi all, Turn up the <"intensity a bit"> and that will at least take low light away from our possible causes of poor plant growth. If the plants really do look pale? You could try a bit more magnesium (Mg), you can buy it easily as "Epsom Salts" (MgSO4.7H20) for baths etc and that is 10% Mg...

...you reach a more <"stable conductivity range">. If you want to reduce the amount of nutrients you are adding? You could use the <"Duckweed Index"> as an indication of when you need to add nutrients. I use regular small water changes with the "Duckweed Index", other people will either...

First of all: Thanks everybody for the feedback :D:angelic::thumbup: Lighting was new with this tank build/setup. My old tank was a diy led with some extra cheap flood lights. At the start of the new tank i had 3 weeks dark start (because of waiting of the plants and other stuff). And the...

Hi all, I'd guess that it isn't a nitrate (NO3-) effect as well. As @PARAGUAY says the plants look a good green and usually the <"degree of green coloration and fixed nitrogen availability"> are closely related. Nitrate testing is quite <"problematic at low levels">, which is why I tend to...

...my floating plants grow well,have good overall colour and leaf shape and relatively short root systems. According to @dw1305 's Duckweed index short roots tells me there are plenty of nutrients in the water and the good colour and shape tells me there are no deficiencies present. As you say...

Would it be worth trying to use some different chelating agent? Maybe EDDHA? I know my PH is around 7.6 so not so ideal as far as availability of iron goes IIRC. I think I've previously seen a thread about dosing EDDHA on this forum and know that you can go off of the tint it gives to the...

Hi all, It is nutrient issue in the tank. The difficulty is finding which nutrient. Years ago I had this, before I really understood much about nutrient deficiencies, one tank where the Frogbit never grew, everything else was fine, just the Frogbit. I always thought it was light or...

...indeed possible, for most home aquarists. That led me to a floating plant (so still with <"Diana Walstad's aerial advantage">) and originally <"Lesser Duckweed (Lemna minor)">, hence the <"Duckweed Index">, and the "duckweed" subsequently evolved into Frogbit (Limnobium laevigatum). cheers...

I think the potential usage for plants with the aerial advantage goes even beyond that. Darrel always says plant/microbe filtration is "belt and braces", what about belt, braces and bootstraps (or something). The reason im still trying to work out a way to include some CO2 unlimited plants in my...

Hi all, Possibly not, you are right on the edge of the pH hardness availability zone for FeEDTA. Have a look at our <"pink tint thread">. Plants need trace amounts of the microelements, so usually the difference is between some or none. Iron (Fe) deficiency is one of the few deficiencies that...

...the light, taking up the excess nutrients, being the only non CO2 limited plants. I agree they are great sentinels a la the duckweed index. However, if you're dosing EI and have CO2 the need for the duckweed index is kinda washed away, especially if you have an over powered, greeater...

Hi all, That is actually a good thing, it just shows you <"have lots of nutrients">, but I agree Duckweed is a <"pita to get rid of">. There is, <"Amazon Frogbit is my preferred "Duckweed">. It was a shame I didn't call it the <"Frogbit Index">, but I'd already <"started writing about it">...

The duckweed index is a useful tool for estimating plant health and fertiliser dosing, you can use other floating plants that are much easier to control like amazon frogbit, as Darrel suggests, but red root floater, water lettuce or another salvinia species like minima are good. All floating...

...You can use <"Ceratophyllum demersum "> as your fast growing stem "stem", it doesn't have any roots, so is easy to thin, or remove. The same applies to the <"Amazon Frogbit">, easy to remove, but with a fast potential growth rate and you can use it for the <"Duckweed Index">. cheers Darrel

Well, knowing upfront that Darrels "duckweed index" was actually meant to be "frogbit index" would have been helpful :lol: ... I know, I know my duckweed actually came in unintentionally with some plants I bought last year... so I am not blaming Darrel (not officially at least :lol: )for my...

You can’t put a price on the Duckweed Index because it’s priceless! It’s free but it’s still Priceless! :-)

...than the older leaves it will be one of the <"non-mobile nutrient"> where lack of causes chlorosis in new leaves. @Happi might have some ideas? Have a look at <"Duckweed Index says.....">, this is iron deficient Amazon Frogbit (Limnobium laevigatum). I can hear them......... cheers Darrel

Hi all, If the new leaves really are that pale on the Hygrophila (siamensis) corymbosa? You are very likely to be suffering from <"iron (Fe) deficiency">. Have a look at <"Iron deficiency and which chelator do I need?"> and linked threads, particularly <"Frogbit taken a turn.....">. cheers...

...via phytoremediation: Current status and future perspectives" Bioresource Technology, 315"> I've thought about this in terms of the "Duckweed index" and I think it doesn't actually matter if leaf greeness is a measure of just ammonium nitrogen and leaf growth a measure of all fixed nitrogen...

Hi all, It does, that is why I use it for the Duckweed Index, in preference to the original duckweed, Lesser Duckweed (Lemna minor), which was always slightly yellow in soft water even when nitrogen levels were higher. It had to be a floating, or emergent, plant to access the 400 ppm of CO2...

...it was an iron availability issue they should still be pale? That one reason I like Amazon Frogbit (Limnobium laevigatum) for the <"Duckweed Index">, it <"is green">. Lesser Duckweed (Lemna minor) would combine <"being green"> with a <"very quick growth rate"> (both advantageous) but it...

...iron (Fe) because of the non-mobile nature of iron within the plant and because Tonina is a slow growing plant. I'm using a <"hybrid duckweed index"> approach at the moment where I add iron regularly, even when the <"Amazon Frogbit Limnobium laevigatum"> isn't obviously iron deficient...

...that will just make it even hungrier. It sounds like you will soon have more ferts, I think that will make things much better. Your "duckweed index" looks pretty good, but I suspect that floaters are very fast at grabbing the available nutrients. The reason I think so is because I once...

Hi all, Could be iron (Fe), magnesium (Mg) or manganese (Mn), they are the three options that <"Chempak Sequestered Iron"> provide and that is because deficiencies of all <"cause leaf chlorosis">. The main difference is that magnesium is mobile within the plant, so deficiencies show in older...

...worried as I will be adding some seeded filter material in a week or so and someone offered to give me some frogbit but that may be a few weeks away as well. I really like the idea of a sentinal plant like the duckweed index. I wonder at what level will plants burn due to ammonia in ppm?

...growth. I'm worried my ottocinclus affinis will starve. I've added courgettes to their diet now, but i need a source of aufwuchs. Trying to get repashy soilent green but it's sold out everywhere. Anyway here's an overall shot of how it looks! And one last picture for the duckweed...

This is why the "duckweed" index is brilliant; Those frogbit looks like they are suffering from deficiency issues. If your dosing full EI and have no Mg, Fe or other micro deficiencies they should look like this picture below - not perfect, but certainly very healthy - this is with full EI and...

...or you can make up your <"own bespoke mix from scratch">. This is what @Happi does, and this allows them to customise their mixes. You can always use the <"Duckweed Index">, where you use the <"leaf colour and health of a floating plant"> as an indication of when to add nutrients. cheers Darrel

Yes, the "duckweed index" works well for gauging nutrients levels - I am big fan! With regards to removing the duckweed, I sort of already went down the route of making it a regular part of my maintenance routine to net every floating plant except for the pennywort and rinse off the duckweed...

I see Frogbites as an alternative to massive water changes. You can dose ferts quite relaxed as you know that the floaters are using them like crazy! The only downside is my red plants that are not so red any more. But BBA has not returned, so Frogbites rule!

Hi all, It would have been a lot easier. In <"some ways Duckweed"> (Lemna minor) is the <"perfect plant"> for the Duckweed Index but it also <"has some limitations">. That is looking very healthy, plenty of nutrients in that tank. We may <"have a solution to your Duckweed removal issues">...

Hi Darrel, Perhaps you should rename it the Frogbit index. I wish your advice on the "preferred duckweed" would have been more obvious to me before this happened :lol: When the duckweed really gets going its really hard to get rid of... its almost out competing my Frogbit. Cheers, Michael

Hi all, You are talking <"to the converted">, I'm a <"Frogbit obsessive">, but it was Diana Walstad's <"aerial advantage"> that led to the <"Duckweed Index"> and eventually Limnobium laevigatum as my <"preferred "Duckweed">. cheers Darrel

...salts it is a lot cheaper. I have made up my own in the past (<"mainly for work">) but now I just use a <"terrestrial fertiliser mix">, fed via the <"Duckweed Index">. I have lean dosing and very weedy tanks so I'm not overly worried about <"using fertilisers containing urea">. cheers Darrel

...for tank health, I would unequivocally recommend it. I understand that, I'll be honest it is all guessing for me. I don't even try and <"work out which deficiency it is"> away from <"iron (Fe)">. I used a floating plant for the <"Duckweed Index"> to take CO2 out of the equation. cheers Darrel

...that algae <"don't have any internal plumbing">, so they show a quicker response for non-mobile nutrients. <"A quick response to nutrients"> (high maximal growth rate) was one of the reasons why Common Duckweed (Lemna minor) was the <"original duckweed"> for the <"Duckweed Index">. cheers...

...Yes you can, you don't have to dose at <"full EI levels">, you can use a <"fraction of EI"> on a regular basis or you can use the <"Duckweed Index">. Plants can only take up nutrients <"as ions from solution">, this is true of all all plants including cacti etc. No, not necessarily. I...

...There is <"an equation">, but you may not consider it simple. Job done. That is why I like a <"complete fertiliser mix"> and the<"Duckweed Index">, you don't need to worry about the chemistry, just watch the plants*. *Edit: I appreciate that some people (men) are <"red-green colour...

Hi all, It does look like bright lighting. That would be why <"I would add a floating plant">, not CO2 limited and used to intense PAR. No, it might not well be <"iron deficiency">, but until we have a picture that shows the actual colour of the new leaves? It is very difficult to say. It...

My anubias new leaves are a dead giveaway for lack of ferts, almost as good a canary as the duckweed index. Just an aside, i have experienced BBA not just as a result of not enough ppm co2, variable co2, inadequate circulation, but also too much circulation and crazy build up near filter...

Hi all, That is the real advantage of the <"Duckweed Index">, you base your fertiliser addition on the <"leaf colour and growth"> of your "Duckweed". You just <"watch the plants">, rather than being reliant on <"micro-managing nutrient addition"> or needing a <"specific type of water chemistry...

Hi all, That is why I needed a floating plant for the <"Duckweed Index">, access to <"atmospheric gases">. cheers Darrel

...longevity (six months to a year) ease (chuck some in under the sand cap) and very low cost (a 4 pound bag will last a couple of years). I use the 'duckweed index' and observation of plants to decide when to add more or dose micros. Shrimp seem to be absolutely fine with the stuff.

...gain and largely aesthetic. I actually add FeEDTA on a fairly regular basis now, purely because Fe deficiency is where the <"Duckweed Index"> has some limitations, in that by the time the <"deficiency is obvious">, it takes a while before new, healthy leaves grow. If you look at @Zeus. 's...

...Those ones really. Personally I don't want optimal plant growth (and lots of stems that need trimming every week), I just want some active plant growth. It doesn't matter whether you use EI or the Duckweed Index, you need to supply all fourteen of the essential plant nutrients. cheers Darrel

...substrates like amazonia. In fact shops will adopt lean dosing for healthy plant growth but less faster meaning less work maintaining 30 or 40 planted CO2 aquariums. A bit different on low dosing regarding low energy no CO2. IME less dosing but dosing all nutrients when needed as Duckweed Index.

...have a good reason to be healthy due to proper maintenance (regular large WC's etc.) I wouldn't worry about it. In addition to the Duckweed Index a good way to monitor overall tank health is to gauge the TDS level over time - if you have gradually rising TDS, due to buildup of waste etc...

...testing is <"not entirely straight forward">. It was partially the difficulty with getting accurate values for nitrate (NO3-) that led me to the <"Duckweed Index"> a technique where you use the health and leaf colour of a floating plant to <"estimate fixed nitrogen availability">. cheers Darrel

Hi all, It would have been so much easier if I'd called it the "Frogbit Index", rather than the "Duckweed Index" , but I'd already <"started writing about it before I changed over"> from Duckweed (Lemna minor) to Amazon Frogbit (Limnobium laevigatum). That would be my guess as well, often...

Thanks Darrel, I'm afraid I read most of what you wrote as hieroglyphics 🤯 sorry, all the science is brand new to me! But I'll go through the links provided, thank you! I have 5 horned nerites and 2 or 3 pond immigrants that ferried over with plants I'd bought...they're clearing up well...

You don't actually have to use duckweed for the duckweed index - frogbit would work great. The fact all your floaters disintergrated might also be a symptom of missing nutrients. You can use a ring of airline floating on the surface to contain floaters and protect them from surface disturbance.

...<"TNC complete"> should do that, although it is possible that you might need to add some more magnesium (Mg) and/or iron (Fe) if you have very hard water (and I'm going to assume you do.) I'm probably both biased <"and obsessed">, but I'd really recommend the <"Duckweed Index">. cheers Darrel

Yes I do love the sun up and sun down modes, I have an hour each. What confuses me is how much of which particular colour to use 🥴 I'll post a screenshot of what the light are working on at the moment, maybe someone can suggest some alterations? I've tried a few floating plants and I've failed...

...the surface to shade below. Your valis will be doing some of that - you might find the algae is a little less under where that floats over the surface? You could introduce some more floating plants and they can be a helpful indicator for plant feed too if you search the forum for 'duckweed...

...of being both smaller and shade tolerant, allowing it to hide, even more successfully, in among the other floating plants. The Duckweed Index is called the "Duckweed Index" <"because originally it used Lemna minor">. I stopped ,"using Duckweed">, because: People have an (irrational)...

A little late to this one...opposed to Darrel, allegedly, I guess my Hairy Arm Index is fairly low (Zn or Fe deficiency perhaps? :lol: ), but here is what I did. Cheers, Michael

...<"oxygen levels">. Red root floater (Phyllanthus fluitans) isn't <"very robust">. I think that Amazon Frogbit (Limnobium laevigatum) and/or Nile Cabbage (Pistia stratiotes) are your best bet. I'm a <"Frogbit fan"> for the Duckweed Index, but Nile Cabbage works just as well. cheers Darrel

...plants, or the more <"difficult juggle"> of high light ~ high CO2 ~ high growth rate. Clive @ceg4048 thinks that all algae issues probably relate to CO2 availability, which was why it needed to be a floating plant for the <"Duckweed Index"> it takes CO2 out of the equation. cheers Darrel

...get out of the tank">, but other floaters like Salvinia "auriculata" (Water fern), Pistia stratiotes (Nile Cabbage) and Limnobium laevigatum (Amazon Frogbit) are much easier to control. I <"really like"> Amazon Frogbit, partially because you can use it for the <"Duckweed Index">. cheers...

...tap water? I'd add them both separately, Epsom Salts (MgSO4.7H2O and 10% Mg) is good as a magnesium source but you would need a chelator for harder water . This is what I'm doing at the moment, in a <"hybrid Duckweed Index"> approach while I'm using <"Miracle-Gro"> as my fertiliser. cheers...

Hi all, I like your thinking. I'm just worried that there are too many variables: Hair length, hair curliness, hair density etc. But a thought occurs, it might be a business opportunity, the "Duckweed Duster Buster" an artificial arm hair sleeve with optimal nylon hair parameters, possibly...

Thank you all for the advice. Given both tanks have significant amounts of emergent plants it sounds like I need to learn to live with it. Darrel, it sounds like there could be a use for a hairy arm duckweed removal index as a corollary to your duckweed index?

Hi all, How are they looking today? This is a <"non-mobile nutrient (iron (Fe))"> but you can see the effect. This is over several weeks, with nitrogen (N) you really can see the leaves get greener over a couple of hours. Before After cheers Darrel

Hi all, This is the major reason why I like a floating, or emergent, plant for the <"Duckweed Index">, it takes <"CO2 (and in nearly all circumstances light) out of the equation">. A floating plant has access to ~ 415 ppm atmospheric CO2 via <"stomata in the upper leaf surface">. All you need...

...thirteen <"essential nutrients for plant growth"> as well). I've not kept CRS, but if I did I'd use <"nutrient depletion"> and the <"Duckweed Index">. If you like it is an <"Orchid Growing approach">. Nitrate (NO3-) isn't toxic at low levels, we don't know what "low" means in terms of...

No the new leaves do not look pale in real life, thats just the brightness of the light, yea i hope with this new DIY ferts i can get rid of the deficiency's Thanks for your reply and info.

...there may still be <"some issues">, particularly with the monovalent ions (NO3- etc.) where they <"form soluble salts">. One advantage of both "Estimative Index" and "Duckweed Index" is that they do away with the need to <"accurately test for potentially problematic parameters">. cheers Darrel

...quickly you would like your plants to grow, I use a technique where I use the <"health and leaf colour of a floating plant"> (the <"Duckweed Index">) as an aid to when I need to add nutrients, others will use a more regular fertiliser addition based on the <"Estimative Index (EI)"> cheers...