Help me identify deficiency in total a so.

[Sarpijk]

Tank is 60litres with pressurised co2 and E.I. For micros I use Seachem comprehensive and Sea hem iron. The light fixture houses a 24watts T5 Sylvania Grolux.

Only new leaves seem unhappy. There is no melting. I feel it is iron related but I believe it might as well be a nitrogen deficiency?

 

[Sarpijk]

Ιs there anybody out there?

 

[bloskas]

is that rotala sp.?! i would go for magnesium deficiency. similar as iron as it it prevents the plant from absorbing iron. maybe your tap water is low on magnesium. maybe it is because you have skipped some micro dosings.

 

[dw1305]

Hi all,

Only new leaves seem unhappy. There is no melting. I feel it is iron related but I believe it might as well be a nitrogen deficiency?

It is a non-mobile element, which discounts nitrogen (N), potassium (K) phosphorus (P) and magnesium (Mg), because they are all mobile and would effect the older leaves first.

I feel it is iron related

That would be my guess. Id your water very hard?

cheers Darrel

.

 

[Sarpijk]

Υes indeed my water is hard and I see the iron precipitating whenever I dose. We had talked about it last year http://www.ukaps.org/forum/threads/precipitation-of-fertilisers-due-to-hard-water.37742/.

I keep dosing Seachem Ιron. I haven't been able to find another chelated iron. I tried looking up the synthesis of Easylife Ferro in case it included a different chelator.

 

[dw1305]

Hi all,

and I see the iron precipitating whenever I dose

OK, then it is very likely to be problems with iron availability. Like "Bloskas" mentions the interveinal chlorosis of the leaves in your photo is characteristic of both iron and magnesium deficiency, and both are often caused by high calcium levels blocking their uptake by the plant.

I would be tempted to try a different chelator.

I think "Seachem Iron" use iron gluconate, they make play of it being ferrous (Fe++) ions, but in hard oxygenated water it will form insoluble ferric (Fe+++) hydroxides etc really quickly. This will be the precipitate you can see.

<"The Krib:Iron gluconate"> (from 1998), is quite an enlightening read.

The problem is that iron is much less strongly bound in iron gluconate (it is complexed rather than chelated) than it would be in FeEDTA, or even better a chelator <"more stable at higher pH values">.

Because iron isn't mobile, the chlorotic leaves won't green up, but new leaves after dosing should be greener.

cheers Darrel

 

[Sarpijk]

On eBay I have found FeEDTA 7% and 11%. Are both of them suitable?

 

[dw1305]

Hi all,

On eBay I have found FeEDTA 7% and 11%. Are both of them suitable?

Should be.

I thought it was normally sold as the the ferric sodium salt (13% Fe - C10H12N2O8 FeNa.3H2O), but it is a reagent we use quite a lot at work, so I don't buy any specifically for the fish tanks.

cheers Darrel

 

[xim]

On eBay I have found FeEDTA 7% and 11%. Are both of them suitable?

I think they might be DTPA. Since most Fe-EDTA powder are 13%.

I personally use DTPA 7%. There is also DTPA 11% but it's not available in my area.
DTPA performs better than EDTA in hard water but the colour is stronger than EDTA.
It will stain your tank water a bit (brownish-green) but no where near EDDHA, this one
is just like putting potassium permanganate into the water, in terms of colour.

All DTPA and EDTA should be OK to use. Even EDDHA if you don't mind the colour,
it's popular among aquaponic people.

 

[Sarpijk]

I just realized that I have a trace mix that contains the following. I will try using this for a while.

 

[xim]

In a trace mix, Fe is the element that is needed in the highest amount.
And Cu is the most toxic element to aquatic animals and plants.
So the ratio of Fe and Cu is an important factor to consider
when looking at a trace mix to use. If the Cu is too high compared to Fe,
you may reach Cu toxicity before getting enough Fe for the plants and vice versa.

I've read some toxicity data but don't have direct experience about it
so I like to look at the ratio of popular trace mixes in this hobby as references.

Tropica's
Fe 0.07% Cu 0.006% = 11.66666666666667:1

Seachem Flourish Comprehensive
Fe 0.32% Cu 0.0001% = 3200:1

CSM+B
Fe 7% Cu 0.1% = 70:1

Your trace mix
Fe 4% Cu 1.5% = 2.66666666666667:1

Quite high Cu I would say. I would use it in conjunction with the
Flourish Comprehensive. Just my thought, though.