Dwarf water lettuce issue

[Gringo]

Hi all,

Does anyone know why my dwarf water lettuce is turning white? I've tried searching but can't find much.

They're at least a month or so old, lights are on for 7 hrs, it's very low tech, the light can be white, blue or both, I did keep it on both for a while but since I noticed it, I changed to just white incase both was too bright for them but hasn't changed at all.

thanks all

 

[dw1305]

Hi all,

Does anyone know why my dwarf water lettuce is turning white?

You can pinch off the older white leaves, the plant has withdrawn the chlorophyll from them.

The plants look OK, but they may be struggling in lower light. There isn't really a <"Dwarf Water Lettuce">, they are all just Pistia stratiotes and capable of growing into large rosettes with strong light and lots of nutrients.

cheers Darrel

 

[Gringo]

Thank you Darrel

I'm learning more and more everyday 👍

 

[dw1305]

Hi all,

I'm learning more and more everyday

I've kept planted tanks <"for a long time">, but <"I'm still learning">.

The problem is really now information overload, and trying to sort out the <"coffee from the froth">.

Have a look at <"Curled and blackened"> and linked pages.

cheers Darrel

 

[tiger15]

Hi all,You can pinch off the older white leaves, the plant has withdrawn the chlorophyll from them.

The plants look OK, but they may be struggling in lower light. There isn't really a <"Dwarf Water Lettuce">, they are all just Pistia stratiotes and capable of growing into large rosettes with strong light and lots of nutrients.

cheers Darrel

I am growing it in my gallon bowl by the window that receives afternoon sunlight. It’s doing well with long hairy roots, leaves not much bigger than frogbit and hope its size can be constraint by the small opening of my bowl. I’ve seen grown ones in ponds that are twice the size of my bowl though

 

[Gringo]

I've removed loads of the leaves that was affected, but after 2 days this has appeared



It looks like a growth of some kind but not sure what 😕

 

[dw1305]

Hi all,

that was affected, but after 2 days this has appeared

I'm not sure, it maybe <"lensing"> if the leaves have been splashed? Also have a look at <"Holes in floating....">.

It might still be a light issue, if you are still on "just white"? Or a nutrient issue.

For nutrients, we can discount iron (Fe), because the new leaves aren't very pale, and CO2 because it is a floating plant, so that just leaves everything else.

What nutrients are you adding?

Because of the fish, and your healthy looking submerged plants, I'm going to assume it isn't nitrogen (N) and/or phosphorus (P), so that leaves potassium (K) and magnesium (Mg) as the next most likely options.

I'm going to assume your water is hard, looking at the fish (very nice C. nanoluteus) and healthy Vallisneria and <"elevated levels of calcium (Ca)"> can effect the uptake of K and Mg.

cheers Darrel

 

[Gringo]

I'm using TNC lite for nutrients, dosed daily along with carbon, that's without phosphorus and nitrate as my phosphorus is 2-3, nitrates 20-40, Kh 6 Gh 13 so quite hard.

I've now put blue and white on to increase the light

If they end up dying I'll probably buy some different floating plants 😕

 

[dw1305]

Hi all,

I've now put blue and white on to increase the light

See what happens hopefully they will show a bit more growth, with more light. If they don't then at least we will be able to discard light intensity as a factor.

I'm using TNC lite for nutrients, dosed daily along with carbon

I might try the <"TNC Complete">, if you are adding liquid carbon it can only increase plant growth if <"all the nutrients required"> for plant growth are present.

my phosphorus is 2-3, nitrates 20-40, Kh 6 Gh 13 so quite hard.

Do you know what the water values for your tap water are? You should be able to get them from your water supplier, which I assume will be <"Severn-Trent">.

Water testing can be a lot <"more problematic"> than most literature and the sellers of test kits would have you believe, the advantage of the water company is that they have an <"analytical lab."> with trained scientists and some pretty expensive kit.

I'm <"not interested in optimal plant growth">, so I don't add nutrient regularly, I actually use the <"health and leaf colour of a floating plant"> as an indication of when to feed.

I called it the <"Duckweed Index">.

cheers Darrel

 

[Gringo]

It's more the white coating I'm concerned with as that seems to be the cause of the leaves dieing.

Just a thought, if food has been stuck on the top, with the humidity and a bit of splash, would this cause mildew? Then that's spread to the other plants eventually killing off the leaves ?

 

[dw1305]

Hi all,

It's more the white coating I'm concerned with as that seems to be the cause of the leaves dieing.

Just a thought, if food has been stuck on the top, with the humidity and a bit of splash, would this cause mildew? Then that's spread to the other plants eventually killing off the leaves ?

It might be Mildew, it also looks a bit like the fluffy white wax that surrounds "Mealybug" eggs, in which case there should be some <"larger Bugs about">?

cheers Darrel

 

[rubadudbdub]

I've had water lettuce for a couple of years and it occasionally does this. I'm sure it's a nutrient deficiency of some kind making the plant sacrifice the leaf. So consequence of poor growth, rather than cause. For me it seems to affect the smaller plants, which is why I thought nutrient deficiency of some kind.

I get it more in the plants I have in a soil tank that I barely fertilise. Thinning the plants out and dosing ferts seems to work. I use aquarium plant food easy EI macro and micro. Dosed according to how the floating plants look. Although I'm a bit slack with the soil tank.

Like Darrel said, it can grow quite large. Given space and ferts mine looks like this under juwel twin 2' t8s

Finally, how do the roots look? Do the platies pick at them? I've given these plants to a friend and his barbs peck at the roots and the water lettuce slowly disintegrates. Maybe your fish are doing the same?

 

[rubadudbdub]

FYI, these are from the same tank pictured above. I had a massive clear out as there was a thick overgrown mat covering the tank. Plus I'm trying to get rid of the duck weed. These plants were stuck in a bucket in the conservatory (and rediscovered today!) in case my friend wanted some more. You can see how after 2-3 weeks they're nutrient deficient and some leaves have gone white and furry like yours, vs the ones left in the tank I pictured previously. I'd not worry too much about the white leaves, but try adding more ferts.

If anyone wants any they're free to collect from Kenilworth, Warks.