Lack of calcium?

[freemann]

[]The same old subject that bothers me all the time.
I have Nasaea, Limnophila aroatica, with curled top leaves.
People suggested strongly it was K so I stoped dosing K throu K2SO4 lowered KNO3 and bought a K test from aquarium landscapes. 4 months latter and N can be 0 and still K can in the 10 ppm range which to me proves that K is consumed in very small amounts in relation to what we add and confirms Roger Millers assumption that in KNO3 there is always some K left even after all NO3 and I quote:

I use potassium nitrate to dose nitrogen and I don't worry about the potassium levels at all because potassium nitrate provides potassium in excess of typical plant demands.
I'll be brief. The N:K ratio used by plants is variable, but several sources boil down to typical ratios of about 1:1.43 N:K When you fertilize you need to provide nitrogen and potassium in that proportion. In addition, you need a small concentration (a few ppm, I think) of potassium that is continuously present in the water. That is so the plants can keep a balance between the potassium in their internal fluids and the potassium in the surrounding water.

When fertilizing we usually work with NO3 instead of N. In terms of NO3, we need to provide the plants with a NO3:K ratio of about 1:0.33. Potassium nitrate provides nitrate and potassium in a ratio of 1:0.63.

For each milligram of nitrate taken up by plants they will also take 0.33 milligrams of potassium; if I fertilize with potassium nitrate then 0.30 milligrams of potassium is left in the water. The amount that is left in the water will build up over time to the point where its concentration is controlled by water changes.)

I am using daily dosing with a dosing pump so all ingredients are dosed in steady doses all the time). I can give you amounts in ppm added daily of all if you want. Tank is a jungle. So Lately I start believing there is something wrong with the amounts of traces I add throu the use of Microplex. I am going to substitute it with Microsal from Brustmann and see what happens. I have a table with comparison of there micro content here:
http://www.bellybean.com/~pave/vario...es_compare.htm

We will see

[Sleepy_lancs]

freemann,

Are you saying that KNO3 has sufficient Potassium that is required by the plants? Additional K2S04 isn't needed?

[geoffrey]

Andrew,

That's what Roger Miller said : )

[vinz]

Remember to take into account the amount of NO3 your tank has without dosing. My arowana planted tank is at 20ppm almost consistently without dosing... so I have to use K2SO4 to maintain K instead of KNO3.

[freemann]

With about 50 small fish in the tank (143 lt) and another tank with prolly more around the same volume the test says so yes there is always more K than the plants can consume, Vinz are you certain the tank is deficient of K have you tested it?
My policy in the tanks from now on is to seperate K from NO3 by using Ca(No3)2.4H2O for NO3 and a bit of Ca (it will increase my Dh one degree every 20 days so no problem with that), and K2SO4 for K by using different pumps for each ingredient I will be able to finetune the output this way I will be able to keep both K, NO3 in the 3-5 ppm range at the most constantly.

I mean look at this one I found:

Author : Brumm, I.; Schenk, M.; Gysi, C.;
Title : Influence of nitrogen supply on the occurrence of calcium deficiency in field grown lettuce.
Source : ACTA HORTICULTURAE, no.339:125-136, 1993.
Language : En, Abst. in En,
Keywords : INDIGENOUS VEGETABLES/ LACTUCA SATIVA/ LETTUCES/ CALCIUM NITRATE/ NITROGEN FERTILIZERS/ PLANT DEVELOPMENT/ DISORDERS/ TIPBURN/ FERTILIZERS/ NITROGEN/ VEGETABLES/
Abstract : In field experiments with lettuce cv. Capitan, the influence of N supply on the incidence of tipburn, a common physiological disorder of lettuce caused by Ca deficiency, was investigated. N as calcium nitrate was applied at rates of 20 to 400 kg/ha. Tipburn increased with N supply in all experiments. This was partly related to an increase in head size, as well as to a specific effect of N. This direct effect of N on tipburn was not accompanied by low Ca concentration in the DM of inner leaves or by changes in head morphology, but by a decreasing root:shoot ratio. The experiments showed additionally that a supraoptimal N supply not only increased the risk of tipburn but also the Nmin residue at harvest in the soil, and thus the risk of nitrate leaching.

Or this mail exchange I had with Krombholz which I hold highly estimed:

[quote]From: [email protected] (Paul Krombholz)
Subject: Re: Hi Paul, calcium deficiency problem?


>Hi Paul it seems your reference in Krib in nutrient deficiencies is the
>only that covers me so i feel like asking for your opinion.
>
>I have a 143 lt water column aquarium 52 days old
>Gh 8
>Kh 13
>Ph 7
>Light is 2,8 watts per gallon fluorescent lamps, 3 osram 21 plus 3 philips tdl
>2 bubbles CO2 per second, Pressure type CO2.
>K around 30 ppm, N 5ppm , P 1 ppm (I added 0,7 ppm twice between water
>changes) and traces microplex plus Mg plus Bo according to Sears.
>Sand size 2-3 mm 8 cm depth, 2 cm forest soil with laterite under it.
>Aquarium bubbles like crazy, all plants grow nicely (exception is mayaca
>that grows really slow but that maybe cause it is in a place with not that
>much light), no algae but just a few leftovers very few.
>My problem is leaf growth in Nesaea crassicaulis mainly but also in the 2
>rotala species not all but most leaves grow in a sickle like shape and are
>curled and distorted from their initial appearance, also older leaves lower
>in the stem turn dark and fall off (the fall of leaves maybe cause of lack
>of light in lower leaves and irelevant). This curled phenomena appears in
>rotalas also but less so it must be some deficiency, also leaves are not
>flat but cuped with the central vein persisting in Nasae.
>Included is a url of a photo please look at it and tell me your opinion.
>URL is: http://www.bellybean.com/~pave/vario...las_leaves.jpg
>It seems that your reference to calcium deficiency describes all of the
>symptoms I see.
>Boron it is said to create the same symptoms but i have added additional
>amounts of it on top of microplex concentration accordind to pmdd instructions
>Could it be that plants cannot extract enough calcium from water hardness
>in relation to their growth speed?
>Gypsum seems the best alternative to add calcium without altering the ph
>will you agree on that?
>Thanks in advance
>Paul in Greece


Hello

[vinz]

Freemann,

The email address you registered is not working, could you check your PMs please?