Rotala Rotundifolia - Growth Issues

[sciencefiction]

certainly iron doesnt cause stunting..

The new growth on the deficient hydrophilla, I posted above, is stunted. That plant grows large green leaves when healthy. When i started dosing iron I cut out all the damaged growth. You can see the size of the leaves on non iron deficient hydrophila on the second picture.

Additionally, the iron deficiency caused the stalks to be very fragile and soft like, and bending easily. When I dosed iron it literally straightened itself up within a day or two....like terrestrial plants that had been lacking water...

 

[aquanick]

Moderate iron deficiency causes lighter colour leaves. Severe iron deficiency causes bleached leaves and stunted, smaller leaf size. Lack of Mg is similar but the leaf veins remain green unlike iron deficiency where the entire leaf is bleached and could even turn slightly pinkish. However, other micro ferts could also be affected by too much Ca++

Does increasing Mg ppm help in cases where rocks leach out Ca++ or the water is hard due to excess Ca?

Also, 3 days of dosing iron and i see improvement in new leaves which are green and not pale, still not full though and look small in size. The old growth has not changed and I assume will not change as Fe is a immobile nutrient?

thanks for all the help..

and sorry OP for taking over this thread..

 

[sciencefiction]

No. The old growth will not change. If the new leaves are greener than there was insufficient iron. The plant will grow to the next limited nutrient afterwards, if any.

 

[dw1305]

Hi all,

Does increasing Mg ppm help in cases where rocks leach out Ca++ or the water is hard due to excess Ca?

You can add more magnesium (Mg), the problems with uptake come about because of the very high calcium:magnesium ratio. It is just a simple numbers game, very few Mg++ ions are taken up by the plant, because they are very rare in solution compared to Ca++ ions, add some more Mg++ ions to solution and more end up in the plant.

Adding more magnesium will raise the dGH and conductivity, but neither of those are a problem if you have a hard water supply to start off with.

Calcium carbonate (CaCO3) is less soluble than magnesium carbonate (MgCO3), so if you exceed to solubility limit (or it changes due to <"increasing temperature">) calcium carbonate (from Ca++ and 2HCO3- ions) will precipitate out before the magnesium carbonate (in solution as Mg++ and 2HCO3-) does, due to the <"common ion"> effect (HCO3- is the common ion).

cheers Darrel

 

[aquanick]

Thanks, Darrel!

So it appears that its a ratio game where either Ca or Mg can be off.. and looking at plant behaviour to dose is the way to go.. curling tips indicate Ca deficiency? Pale growth indicates Ca surplus causing Fe blockage and dosing Mg helps?

Seems odd so many hobbyists call rotala as a weed (grew like a weed in all my previous setups) and so many have the twisted and deficient growth issues..

 

[rebel]

@dw1305, Do you think that it's best to dose CaCl because of better solubility?

I thought the ratio thing may not apply to aquatics? @plantbrain had suggested that the ratio thing doesn't apply in a practical sense?

 

[sciencefiction]

curling tips indicate Ca deficiency?

It does in terrestrial plants. I am not so sure underwater plants have the same response to lack of Ca++ I wouldn't be sure in that though because I don't think I ever dealt with that. I've seen curled tips in my emersed plants for a period of time though but it certainly wasn't lack of Ca++ You can also have curled/stunted new growth due to severe lack of nitrogen and I think that's what my issue was then but when nitrogen is the problem, the old growth is also affected.

And adding magnesium sulphate to an iron deficient hard water tank did nothing for me. It was the first thing I tried years ago when I first saw the pale leaf growth all over my plants after getting some advise here. Magnesium is a mobile nutrient. It affects old leaves, not new growth. And its pretty easy to distinguish because the veins remain green, except for in anubias because for a period of time it may appear similar to iron but the difference is whether new or old growth is affected.

 

[dw1305]

Hi all,

Do you think that it's best to dose CaCl because of better solubility?

The advantage of calcium chloride (probably in use as the hexahydrate CaCl2.6H2O)) is that it is highly soluble, in fact if you expose it to enough atmospheric moisture it will dissolve itself in the bag.

I thought the ratio thing may not apply to aquatics?

You would have to ask Tom, I think that was specifically to do with debunking the <"Redfield ratio"> of N as a source of algal growth.

My understanding is that low levels of Ca++ ions increase the uptake of Mg++ ions, but as the level of calcium rises this is reversed. The reference would be <"Magnesium mobility in soils as a challenge for soil and plant analysis, magnesium fertilization and root uptake under adverse growth conditions">, but it draws on the work of Olsen (1942) on nutrient uptake from hydroponic solution.

In nutrient solution experiments it has been shown that high availability of the cations Ca, K and Mn can lead to strong decreases in Mg uptake (Marschner 2012). Fageria (1973) reported on the effect of increasing Ca concentration in a nutrient solution on the uptake of Mg and K by rice plants (Table 1). The author showed that increasing the Ca concentration to a certain level increases the uptake rates of Mg (and also K, not displayed here). It is assumed that at very low availability of Ca (Ca deficiency) the plasma membranes of root cells are adversely affected leading to ion leakage and unspecific uptake. Slightly increasing the Ca concentration in the nutrient solution then rapidly restores the membrane functionality, so that the uptake of other cations is enhanced and leakage reduced. Further increasing the Ca concentrations in the nutrient solution then turns the positive synergistic effect of the nutrients into an antagonistic cation competition for uptake. This is reflected by a reduction in uptake of Mg (and K) when the Ca concentration in the nutrient solution is further increased.

cheers Darrel

 

[dw1305]

Hi all,

debunking the <"Redfield ratio"> of N as a source of algal growth.

Sorry about the emoticon, I forgot to put a space between N : P, and "colonP" gives you a pink smiley face .

cheers Darrel

 

[Seoulstar]

Blyxa jap after 3 days on planting turned pink with leaves melting away..

Specs:
1.5ft tank with co2 from reactor and plants pearl like crazy so i am sure co2 is not an issue

Ferts : EI using dry salts ( kh2po4 and kno3) and a hydroponic mix of micros. I completely stopped micro dosing reading this happens with toxicity.

For a week i got some improvement after dosing MgSO4 thinking Ca: Mg ratio was off.. however things have reverted back to being worse..

Need help guys..!

This is so interesting because my plants looked exactly the same, then I also saw some improvement after dosing more Mg but then it got worse again.

Did you ever find a solution or are you still trying to work things out?

 

[dw1305]

Hi all,

then I also saw some improvement after dosing more Mg but then it got worse again.

Magnesium (Mg) is mobile within the plant so adding it (when it is deficient) causes a rapid greening, because the plant can move it to where it is required.

When you have a deficiency of nitrogen (N), potassium (K) or magnesium (Mg) you will probably have chlorotic, yellow, leaves and these symptoms will initially show in the older leaves.

Your plants may have been deficient in more than one element, although only one will be limiting for plant growth at any time. If magnesium was the limiting nutrient, and you supplied it, the next deficiency symptom may show.

If the next deficiency is of a non-mobile element, like iron (Fe), it will effect the growing point, and you won't get any greening of the older leaves when you add the deficient element, but new leaves, produced after the iron etc. addition, will be greener.

How much of each element is required is going to depend on the plant, and how rapidly it is growing. A potentially quick growing plant, which is supplied with abundant light, CO2 and mineral nutrients, may show deficiency symptoms at a relatively high absolute level of the limiting nutrient.

cheers Darrel

 

[Michal550]

Hi Konrad.
How is the rotala doing?

 

[Konrad Michalski]

Hi Konrad.
How is the rotala doing?

Definitely better than it was. It still ain't perfect but slowly getting there.

 

[AndreiD]

Looking good , what did you change ?

 

[Konrad Michalski]

Looking good , what did you change ?

I mentioned before - I've stopped dosing Potassium.

 

[MrHidley]

I'm really glad to have learned this, my rotala in a previous tank had the same short fat leaves.

 

[Konrad Michalski]

I'm still not 100% happy with the look of it and will be making some adjustments to eventually say - yes, this is it. But now I will be mainly working on the colour.

 

[AndreiD]

I'm not 100% convinced that the potassium was the issue , however i can see you have phosphate deficiency , can see it on monte carlo leaves , you have small GSA dots .

You did 2-3 water changes per week during this period ? (when rotala started to get better)

BTW , you say that you are not happy with the look of it, what do you expect them to look like?

As i said a few posts before , i had the EXACTLY the same problem than you with rotala , and i'm dosing 15 ppm KNO3 , 2.5 ppm KH2PO4 , also micros 3 times per week 0.3 ppm three times per week , and only when i switched micros from EDTA (chelated traces) to DTPA (Easy life profito) rotala was recovering .

Its not a CO2 issue 100 % because during this period , when rotala was recovering and started to dose Profito , i was turning CO2 down from 2.5 bps to 1.5 bps .

I'm curios if you did more water changes than you do normal , because if you did than this explains why rotala was doing better

 

[Konrad Michalski]

I'm not 100% convinced that the potassium was the issue , however i can see you have phosphate deficiency , can see it on monte carlo leaves , you have small GSA dots .

You did 2-3 water changes per week during this period ? (when rotala started to get better)

BTW , you say that you are not happy with the look of it , how do you aspect to look like ?

As i said a few posts before , i had the EXACTLY the same problem than you with rotala , and i'm dosing 15 ppm KNO3 , 2.5 ppm KH2PO4 , also micros 3 times per week 0.3 ppm three times per week , and only when i switched micros from EDTA (chelated traces) to DTPA (Easy life profito) rotala was recovering .

Its not a CO2 issue 100 % because during this period , when rotala was recovering and started to dose Profito , i was turning CO2 down from 2.5 bps to 1.5 bps .

I'm curios if you did more water changes than you do normal , because if you did than this explains why rotala was doing better

Andrei I spoke to the person on another forum who recommended this to me as that solved her problems. Since stopped dosing potassium it has started slowely recovering so I cut affected stems and when new one started growing they were fine. I wasn't doing additional water changes at all.
Those green dots were on the old leaves in the corner somewhere. That's how it looks normally but bare in mind I have 4x39w of light

I've not been dosing potassium for about a month and test still shows 12-14

 

[AndreiD]

Ok , i understand , i have 2 x 24 W lighting on my 64 liter tank .

Can you please tell me what are you dosing now ? macros and micros and how much in ppm if possible .

I want to try this dosage on my tank since i have rotala and monte carlo aswell .

Thank you .

BTW how is your hygrophilla pinnatifida doing ? do you have pinholes in old leaves ?