Plant deficiency : Iron ? Mg ?

[Benjamin61]

Hi Everybody !

I need you expertise, I don't know which plant deficiency has my tank (160 liters).

Staurogyne Repens : Leaf tissues are yellow on old leaves. New leaves growth yellow.
Ludwigia "super red" : Old leaves have holes and leaf tissues are yellow or black, new leaves curled.

Ferts for 160 liters :
- Easy Life Profito : 15 ml / week
- Aqua Rebell NPK : 30 ml / week

Water tests (I use 100% tap water) :
- GH : 10
- KH : 8
- CO2 : 25 mg/l
- NO3 : 10 mg/l
- PO4 : 0,5-1 mg/l
- K : 20-25 mg/l

Lighting :
- 7h photoperiod
- Led 44W with dimmer set to 90%

Circulation flow :
- External filter 950 l/h (with inline CO2 diffuser JBL ProFlora Direct)
- Ciculation pump 1000 l/h

I attached 4 pictures.

Many thanks for you helping !

 

[Edvet]

I don't expect deficiency, Profito should cover that.
Some here will say to much light for your CO2 levels. You won't have 25 mg CO2.
I would add some floaters and decrease light to 6 hours, bot will lessen the need for CO2. Floaters will give you a good idea if there are deficiencies because they are in contact with plenty CO2 in the air.
You could use EI micro's ( CSM-B) to make sure you got all.
Are you adding CO2 in any way?

 

[Benjamin61]

Thanks Edvet !

I have a Dennerle CO2 kit, you can see my permanent test on the last photo and below. I add Easy Life Carbo every day too.

 

[Iain Sutherland]

Looks like a lower levels flow issue meaning co2 and other nutries aren't reaching the lower parts of the tank.

If it was a nutrient deficiency ,other than co2, then it would also show on the tops of the taller plants which look healthy.
The top down shot of the stauro also shows a lot of detritus on the gravel, again an indication of poor flow.

If you move the drop checker to a low level at the back of the tank I would bet it is blue or dark green.

Sent from my SM-G950F using Tapatalk

 

[ian_m]

Any "mechanical damage" to plants, holes, tatty edges etc, is either fish munching or insufficient & poor CO2 for your light levels.

What is your filtration rate ? (Filter should be at least 1600l/hr for a tank your size).

How is flow distributed ?

 

[Benjamin61]

Thank you everybody !

I just to move the drop checker on the bottom 😉 I have a external filter 950 l/h and circulation pump 1000 l/h. I use a inline diffuser CO2 (JBL ProFlora Direct).

I must to move my filter output to the down ? which is the best position for the circulation pump ?

 

[dw1305]

Hi all,
I can't tell from the plants, but adding some magnesium (Mg) won't hurt.

You can use "Epsom Salts" (MgSO4.7H2O) as your Mg source, they are ~10% Mg.

Floaters will give you a good idea if there are deficiencies because they are in contact with plenty CO2 in the air.

New leaves growth yellow.

If you see the same symptoms on a floating plant you could have an iron deficiency. Yellow (chlorotic) new leaves are a sign of the lack of a non-mobile nutrient, and there aren't many of these.

Most of the other options for yellow leaves, nitrogen (N), potassium (K), magnesium etc. are mobile within the plan and will effect older leaves first.

Iron deficiencies are much more likely in harder water.

As @Edvet says using a floating plant (with access to 400ppm CO2) takes CO2 deficiency out of the options. I use Amazon Frogbit (Limnobium laevigatum) as my <"Duckweed of choice">.

Have a look at <"Duckweed Index says Nitrogen please?">. If you get Frogbit that looks like this below, iron is your answer.



cheers Darrel

 

[Benjamin61]

@dw1305 Thank you, I will check to buy some Mg

I moved my drop checker 2 times. First, on the front bottom of the tank, this is the result after 2 hours :



In the second time, I moved drop checker on the back at the bottom. This the result after 1 hour (behind Ludwigia) :



According to the drop checker, I have more CO2 in the bottom then the top of my tank. Very strange.

I just tested my water with JBL Test Mg, the result is 1 mg/l but I don't know if this test is reliable...

Regards,

 

[Edvet]

Dropchecker has 4KH solution in it?
( and btw i trust the plants more then the dc)

 

[Benjamin61]

I use this one : https://www.aquasabi.com/co2/co2-drop-checker/dennerle-special-co2-indicator

 

[Edvet]

Fact stays: the lower plants look worse then higher up, has all the earrmarks of CO2 distribution problem.
Lowering the lightlevels will lower CO2 demand, but flow needs to be adressed probably.

 

[Benjamin61]

Hi,

Thank you, I will do that and I come back to you later !

Can you give me an advice for the water flow ? position of the pump, direction of the filter output...
Is inline CO2 diffuser the best way to diffuse CO2 ?

 

[Edvet]

For optimal flow in larger tanks a spraybar is often the best solution, with a circulation pump helping that flow. We aim for at least a 10 times turnover of tankvolume (this keeps in mind the often overrated claims form filter manufacturers regarding volume) *. It takes a lot of experimenting and tweaking to get the flow optimal, and then plantmass comes to disturb it again😵.
The best difusion is experimenting too. A diffusor can work, with the bubbles in the filter intake, or a reactor. Large tanks need a lot of CO2 to get to higher levels.