Search results for query: duckweed index

...of when to feed. Originally I used <"Lemna minor (Common Duckweed">), because it has an even quicker turn over of leaves, hence the <"Duckweed Index">, but it has a <"number of disadvantages"> and my <"duckweed of choice"> is now actually Amazon Frogbit. I don't think that is algae, I think...

Thanks for the clarification Darrel and all of your help👍. How do you think my Salvinia Aruculata will work? I also have Red Root Floater on the way too but, won't have any Amazon Frogbit until my big tank gets here.

...suitable for every plant">. Have a look at <"Glasshouse "floating weeds" tank."> It really has to be a floating plant to use for the Duckweed Index, so that it isn't CO2 limited and it is only Lemna minor or L. gibba that goes that really dark green under large nitrogen loadings. That is...

Roger that. Definitely going to be mixing my own eventually. Interesting. Where can one get one of those colour cards? Learning to read my plants for signs of deficiencies and compensate with ferts is at the top of my learning list right now. I like Frogbit too and can't wait to get some along...

...an ion, the plants don't care how much they cost. Have a look at the <"The scientific background to the "Leaf Colour Chart""> and <"Duckweed Index">. I use leaf size and colour, in a non-CO2 limited plant, as an indication of when, or whether, I need to add nutrients. Others will add more...

Thank you so much!! this is super helpful. I'll deffo be doing some more reading tonight! Sent from my SM-G950F using Tapatalk

...floating plant (ideally <"Amazon Frogbit"> (Limnobium laevigatum)) as my <"nutrient "canary"">. Because it is a floating plant it has access to <"~415 ppm atmospheric CO2"> and its growth isn't ever CO2 limited. Have a look at the <"Duckweed Index"> for more details. Happy reading cheers...

As you should Darrel 😎 Using the tap for remineralising definitely. Gave James’ remineralisation a whirl previously to see if there’s anything more worthwhile trying. Then, realised quickly that this was the wrong question. Unfortunately stuck using RO rather than rain water as it hardly...

Hi all, I'm taking <"credit for this"> (as well as for the <"Duckweed Index">) I honestly think that using your hard, alkaline tap water as your <"remineralising agent is a no brainer">. You aren't going to use very much, so even if you have (justifiable) concerns about the nitrate (NO3-) and...

...it <"suits my morning routine">. When I had more fish I used to change a bit more water, but still use the conductivity datum / Duckweed Index as a guide to whether I was changing enough water. If I've been away from home for a while I'll do a bigger volume water change and I've never...

Hi all, That was partially why I started using a datum <"conductivity range">. Conductivity isn't the most useful measurement, but it has certain advantages, because the meters are, <"relatively cheap">, <"plug and play">, you can just dip them in and get an accurate reading (but you may...

Thanks for your advice Darrel. I might go for the TNC Complete then as the Solufeed looks a bit complicated. I will start reintroducing the macro / micro ferts now then

...out of you. TNC complete is fine. In terms of fertiliser I'm using Solufeed 2 : 1 : 4 (<"from earlier in the thread">) and the <"Duckweed Index">. Just add enough fertiliser to <"keep your Frogbit"> looking like it did in this photo. Solufeed isn't an aquarium fertiliser, and contains...

...cores. The <"Trophic Diatom Index">. This is an algal bioassay paper that touches on both <"the plants can't lie"> and the <"Duckweed Index">. "Novel use of the alga Pseudokirchneriella subcapitata, as an early-warning indicator to identify climate change ambiguity in aquatic environments...

...ability to <"persist at low nutrient levels"> was one of the reasons I swapped to Limnobium laevigatum (from Lemna minor) for the <"Duckweed Index">. We have talked about different nutrient in terms of <"Orchids, Bromeliads and Tomatoes"> (and <"turned up to eleven"> plants). I really don't...

...tissue formed when iron isn't available <"will always be chlorotic">. The non-mobility of iron is why I've moved to using a <"hybrid Duckweed index">, where I add iron on a regular basis. This is @Zeus. 's "Future of Aquascaping" picture, where the iron has been turned off and on. Cheers...

It truly is your favourite..., isn't it? :D But I agree, it's a smart analytic tool, in this case and in general.

...you can check whether it is the substrate, or lack of fertilisers, and that is to <"use a floating plant">. Have a look at the <"Duckweed Index">, it is a method where <"you add fertilisers"> only when your "Duckweed" growth slows to an unacceptable level. At the moment I'm using...

...what we say, or think, and it <"really, really p*sses me off">. Personally I realise I've been flippant, at times, about both the <"Duckweed Index"> and <"Cycling">, but they have an <"under-pinning of science"> and there is a valid scientific rationale for why they might work. In terms...

...like? Assuming they all look OK? Then I wouldn't worry too much. I actually think the values from the <"leaf colour chart"> and <"Duckweed Index"> are a pretty good proxy for nitrate content in the plant. Try diluting the tank water before you test it, ideally with RO, but if you don't...

You got beaten to it man. Meet the "pump in a tupperware":

1. lack of light - yes 2. lack of CO2 - no 3. lack of oxygen 4. elevated dissolved organic compounds in the water column 5. high oxygen demand in the substrate, i.e. too much easily degradable particulate organics in the substrate. I oxygenate water permanently, so I keep CO2 always low but not...

...I'm definitely going to build the hype up slowly for <"Pump in a Bucket">, before adding in lots of different <"variations on a theme">, <"James Dyson"> style. Going <"too big, too early"> was the mistake with the Duckweed Index, that and not patenting a "new improved" duckweed. cheers Darrel

...Limnobium laevigatum is a pretty good indicator of nutrient deficiencies, which was why it became my <"preferred Duckweed"> for the <"Duckweed Index">. It always had to be a floating plant, to take CO2 out of the equation, and originally it was Lemna minor, but that has a <"number of...

Hi all, That is interesting, do you re-mineralise it? @jameson_uk 's threads have been really useful. I'm sure he won't mind me mentioning that he is red-green colour-blind, which makes the colour element of the "Duckweed Index" a lot more problematic. cheers Darrel

...right. Amazon Frogbit (Limnobium laevigatum) is actually the <"plant I use"> to help and <"diagnose nutrient deficiencies">, via the <"Duckweed Index">. Have a look at <"Frogbit taken a turn">, it shows a complete cycle from chlorotic to healthy. Because the <"chlorosis is in the new...

...would be Amazon Frogbit, mainly because it has a <"nice green leaf"> which means I can use it as my <"Duckweed"> of choice for the <"Duckweed Index">. I like "Hornwort" (Ceratophyllum demersum) and "Indian Fern" (Ceratopteris "thalictroides"), they are <"sub-surface floaters"> and easy to...

Hi all, They are "inflated sheaths" and they act as floats. <"It is a p.i.t.a."> I'm assuming that it (the Lemna minor) was a bit yellow because of the soft water, both Hygrorhyza aristata and Phyllanthus fluitans looked healthy. cheers Darrel

Hi all, I did say <"I'd write articles"> about <"cycling", <"water chemistry"> and the <"duckweed index"> and I still haven't really done any of them. I just need a tranche of time to get the references up to date and work up what I've already got. I still refer back to the one I wrote about...

Absolute stable levels of nutrients was not the intent of EI, but rather "The focus of EI is to ensure that the plants never lack any of their required nutrients. " I still don't see this aim being affected by say 10 ppm NO3 the first day after water change. Many plants won't have issues, but...

Hi all, Yes I'd agree, there are a lot of deficiencies which <"are difficult to diagnose">, but I think iron (Fe) is possible, mainly because there aren't many nutrients that are <"non-mobile and cause chlorosis in new leaves">. You also have probability on your side, due to the difficulties of...

Darrel I will have to dig up some of my conversations with Barr on this topic. I have them but not at my fingertips. It has to do with the very small relative amounts that we use. Like I said I know many of the best in the hobby who routinely dose macro/micros together and have no issue with...

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...