Hygrophila leaves are white-ish

[Flowerhorn_K]

Hi,

My hygrophila has grown in quite dense and nicely, but the leaves are turning a white ish colour. 

I use the tropica root tabs, and I recently started dosing with the tropica premium nutrition liquid fertilizer. 

Is it a mineral deficiency? 

[Seattle_Aquarist]

Hi @Flowerhorn_K

Below is your fist photo enlarged and enhanced with a couple of arrows added.


Before I go into what I suspect is wrong could you please answer a few questions for me?

1)  You are using Tropica......are you located in Europe?

2)  What is the white substrate at the bottom of your tank?

3)  Do you have any water parameter information?  Specifically pH, dKH, and dGH would be helpful.

-Roy

 

[Flowerhorn_K]

@Seattle_Aquarist

1) yes based in Europe

2) It's gravel

3) pH is 7.2, I don't know my dKH, dGH

[Seattle_Aquarist]

On 4/6/2022 at 11:07 AM, Flowerhorn_K said:

@Seattle_Aquarist

1) yes based in Europe

2) It's gravel

3) pH is 7.2, I don't know my dKH, dGH

Hi @Flowerhorn_K

Tropica products are not as common here in the U.S. as they are in Europe, that is why I asked.

Tropica Nutrition Capsules contain two of the three macro-nutrients (nitrogen, phosphorus)  but is missing potassium.  No information is available on the type of iron is being used, just that it has some in it. 

Quote

Nutrition Capsules is an extra nutrient supplement – use tweezers to place the capsule in the gravel, close to the roots of fast-growing plants.

Nutrition Capsules contain both nitrogen, phosphor, iron and micro nutrients.

• The nutrients are slowly released as the plants need them.
• Use Nutrition Capsules for stem plants, Cryptocoryne, Echinodorus, Vallisneria etc. – all plants with sturdy roots.

Tropica Premium Nutrition contains no macro-nutrients put again iron (unspecified type) and micro-nutrients.

Quote

• Contains iron, magnesium and vital micro nutrients
• Does not contain nitrogen and phosphor
• Suitable for aquariums with few or slow-growing plants and many fish

Considering the ingredients in what is being dosed the plants look good but there are definite issues.  Let's address the one you inquired about first, "the leaves turning whitish in color".  Pale/whitish leaves can be caused by a number of factors however the two most common ones are insufficient available nitrogen and insufficient available iron. 

If you have not been dosing the Nutrition Capsules at the recommended dosage or as often as recommended please start doing so.  That should improve the availability of nitrogen. 

As for iron, which appears to be the primary issue based upon the prominent interveinal chlorosis (dark leaf veins with light areas between) on the newest leaves in your photos.  If the iron insufficiency becomes extreme enough the new leaves will actually emerge almost white in color.   But you say "I am dosing iron in both of my fertilizers how can I have insufficient available iron?"  Notice I am not saying you are not dosing enough iron, I am saying there is insufficient iron available.  How can that be?  There are many forms of iron that are used in fertilizers, the most common is EDTA chelated iron because it is the least expensive.  Unfortunately EDTA iron becomes increasingly unavailable to plants as the pH increases above pH@6.2.  By the time the pH approaches 7.2 less than 10% of the iron in solution is available to the plants resulting in iron deficiency.  (See chart) (See description of iron deficiency)


 

Quote

Interveinal chlorosis on young leaves.

a. Interveinal chlorosis on young leaves with larger veins only remaining green (arrow #1). Necrotic spots usually absent; however, with extreme deficiencies, young leaves are almost white (arrow #2) and may have necrotic margins and tips; necrotic spots may extend inward. potassium, zinc or copper excess can inhibit uptake of iron. High pH may also induce iron deficiency....iron deficiency

Iron deficiency symptoms are similar to those of magnesium deficiency, but iron deficiencies occur in young leaves first: Iron accumulated in older leaves is relatively immobile in the phloem.

Unfortunately I don't believe Tropica offers a product that will resolve the issue so I am going to recommend Seachem Flourish Iron which I believe is available throughout Europe.  Seachem Iron is made from ferrous gluconate which is iron in a form that plants can readily uptake even with pH levels above 7.0.  Start by dosing the recommended about on the bottle 2X per week.  Do this for four weeks and watch the new leaves as they appear; do not watch existing leaves they will improve very little if any. By the time the 2nd or 3rd set of new leaves arrive you should start to see a definite improvement in the green coloration and health of you leaves.  It is likely you will also see an improvement in the growth rate of your plants.  I do recommend picking up test kits for carbonate hardness (dKH), general hardness (dGH) and nitrates (NO3) and keep them on hand. Keep us posted as things progress, if you have additional questions just ask.  Hope this helps! -Roy

 

Edited April 6, 2022 by Seattle_Aquarist

[Flowerhorn_K]

@Seattle_Aquarist

Oh wow that was a really amazing answer! It was really interesting!

I really appretiate the effort you put into helping me. I'll be going to my lfs on Friday, so I'll pick the Iron supplement. 

Thanks very much!

[Seattle_Aquarist]

Hi @Flowerhorn_K

How's the new growth on your plants looking? -Roy

[Flowerhorn_K]

@Seattle_Aquarist Hey, it's funny you ask cause I was just thinking yesterday to give you an update ahaha.

I have been dosing iron and potassium for the past 3 weeks, and they definitely look a lot healthier. Some of the old leaves look more green and healthy, and new growth looks good too. Still figuring out if I need to increase the dosage for the tank as a whole but for now I'm slowly increasing week to week and seeing how the other plants do as well. 

[Seattle_Aquarist]

Glad to hear things are improving @Flowerhorn_K, post a pic of the new growth when you get a chance so folks can see the difference.  Once you hit a dosing level where new growth looks good an healthy there is no need to increase the dosage.....overdosing nutrients can have a negative effect as well.  -Roy

[Flowerhorn_K]

@Seattle_Aquarist Here are the update pics! 

[Seattle_Aquarist]

On 4/28/2022 at 8:18 AM, Flowerhorn_K said:

@Seattle_Aquarist Here are the update pics! 

I don't know about you @Flowerhorn_K but I would say that new growth (remember we watch the new leaves....not the existing leaves) is a substantial improvement over what was going on 4 weeks ago.  I can almost see exactly when you started dosing the Seachem Iron about 2 - 3 leaf pairs ago....good work! -Roy