# potassium deficiency



## Anafranil (Mar 15, 2005)

Can lack of K+ cause severe algal growth when all other parameters are optimal? and when dosing extra KSO4 algae started decreasing in a couple of days and the second day new shoots started appearing.Is this possible for K+ to has such influence on plant growth even when Po4,No3 optimal?


----------



## Laith (Sep 4, 2004)

Yes it can.


----------



## Anafranil (Mar 15, 2005)

I came from home now and I couldn't believe my eyes,algae almost gone and new shoots in every plant.The plant growth was stunt for almost a month and all these things happened in a couple of days.I was keeping po4,no3,co2 constant at optimum levels but I didn't paid attention to pottasium.I thought I was dosing enough through Kno3,it seems it was not enough though.Since I completed the NPK the algae was gone.


----------



## HeyPK (Jan 23, 2004)

You are lucky your fish didn't die. I keep guppies, and I have seen that they are stressed when the plants are K deficient. They can get white growths on their skin, and can die from this if potassium isn't increased.


----------



## dennis (Mar 1, 2004)

Paul,
Is this because lack of K causes a slowing in the uptake of NO3. High NO3 levels _can_ be very dangerous to fish.

Anafranil,
Glad your plants and tank conditions are improving. Did you also increase trace suplimentation? How much K were you dosing from the KNO3 and KH2PO4(assuming that was your P source)? I dose 8mg/l NO3 and .375mg/lPO4 4x week and that gives me 20mg/l K a week for an N/P/K 32/1.5/20.6.


----------



## HeyPK (Jan 23, 2004)

No, it is not a problem of high NO3. I have measured nitrate levels (LaMotte kit) in potassium deficient tanks where the guppies were sick, and the readings have been as low as 0 and only as high as 5ppm. The symptoms in the guppies develop too rapidly for NO3 to get high because the plants are unable to take up NO3 because they are potassium deficient. When K drops down to levels too low to measure in my tanks, the guppies become listless and somewhat pale. They do not eat as much. The white skin growths show up in only a few of them. When K is added, the guppies recover their appetite, color, and vigor within hours. The skin lesions take longer to recover. Two or three days may pass before the white patches (probably bacterial growths) start to fade. 

All the symptoms in the guppies except the white patches are subtle. The colors are only slightly faded. Activity and appetite is only slightly reduced in most of the fish. When they think food is coming they still get very active. The listlessness can be seen better when they don't think food is coming. I can see the recovery when I am looking for it. They dash about more even when they are not anticipating food. Usually I don't notice anything is wrong with the guppies until I see one with a white skin lesion. Then, I look more carefully and see that some of the others look a bit pale, underfed and listless. Then I test for potassium and get a zero reading. 

The LaMotte potassium kit is worth getting. It has enough reagents for hundreds of tests.


----------



## Anafranil (Mar 15, 2005)

I might be getting some serious informations here,a week ago I lost 20 cardinals with white patches and torn fins especially when they were near death.I loosing one by one until they were all gone,I've lost a couple of shrimps a few days ago that turned white.I am very possitive that nothing else goes wrong with my water parameters.On the other hand most of the retailers keep their their cardinals in local water of gh 20 and ph 8.8 and K free.....

Now back to fertilization,I was only recently introduced to dosing macros(until now I've been struggling with algae)and haven't developed dosing srategies yet nor have I studied EI or PPS.I still work with test kits to keep Po4 around 1ppm and no3 around 10-20ppm.For K+ is an estimative job done by basic chemistry calculations and a balance or using the fertilator.It's time though to develop a dosing strategie if I want to have stable parameters.


----------



## HeyPK (Jan 23, 2004)

My experience with guppies indicates that the plants can get the potassium levels low enough to kill the guppies if the situation is not remedied. If local dealers are keeping their fish in the local water, my guess is that it isn't completely potassium free, and that there is enough to keep the fish alive. Very likely the local dealers do not have their fish in planted tanks, and there is enough potassium to keep the fish going. We would need more sensitive tests for potassium than our kits give us. 

I found the potassium levels to be unmeasurable with my kit in the San Marcos River in Texas, but there was an abundance of plants in the river as well as fish. A planted tank has a lot of plants in a small volume of water. In comparison, a river or pond has a very large volume of water in relation to the volume of plants. My guess is that when the K level gets down to the point where there is no cloudy precipitate formed with my test kit, there is still enough for the fish, but the plants continue to pull the K level much lower and then the fish get sick. 

I currently have a tank where the K recently got low enough to affect the guppies. I had one female develop the white spots. I added a mix of nutrients including potassium that should have gotten the K level up to 1.5 ppm. The next day, my kit tested zero, and the kit is sensitive enough to give a positive test with 1.5 ppm. I concluded that the plants had already pulled the K level below the sensitivity of the kit in only 24 hours. I added a larger dose of potassium, enough to get the K level up to 12 ppm. Two days later (yesterday), the female with the white spots was beginning to look better. The spots were looking smaller, and the female was more active and was eating. I have not done a test yet on the water, but I think I will today. 

From this result, it looks like the plants can pull potassium out of the water quite rapidly.


----------



## Simpte 27 (Jul 16, 2004)

This is a shot in the dark but it sounds like your tank has (had), columnaris. Potassium is a key ingredient in fighting off this disease. From your description of the white patches, it sounds like it. It can kill very quickly, sometimes even before symptoms show, especially in less hardier species (neons). Could also have been NTD (Neon Tetra Disease).


----------



## HeyPK (Jan 23, 2004)

I am not sure. I used Google and looked at a lot of pictures of columnaris infection, and in all the pictures, it looked more diffuse, more like broad infected patches. In my guppies, it shows up as a raised white spot, too big to be ich, and not round like ich. Also, ich starts out as small spots that get larger. This appears at about the same size it is always going to be. The infected fish I have was getting better yesterday, but I will see if I can get a picture today.


----------



## Anafranil (Mar 15, 2005)

The new fish I've lost,probably of columnaris,with white patches were cardinals and were transfered from 20 gh to 3 gh.They are cardinals and it's the second time I loose cardinals in this way.How sure can I be that is caused by the chenge in water conditions?Secondly I'm loosing shrimps this way,should I suppose the same thing?


----------



## HeyPK (Jan 23, 2004)

It was too late to get the picture. The white spots were all gone on the infected fish.


----------



## plantbrain (Jan 23, 2004)

If you are dosing with KNO3, it's unlikely, although possible, that there is more than enough K+ derived from that source. 
Low SO4 can cause issues, but is rare.

Regards, 
Tom Barr

3rd annual Plant Fest July 8-14th 2005!
[email protected] Get connected
www.BarrReport.com Get the information


----------



## dennis (Mar 1, 2004)

plantbrain said:


> If you are dosing with KNO3, it's unlikely, although possible, that there is more than enough K+ derived from that source.
> Low SO4 can cause issues, but is rare.


 Tom, sorry but I don' quite know if I am reading this right. Just to be sure, you are saying KNO3 *should* provide enough K or that the KNO3 *does not* provide enough K?

Aside from K2SO4, what other sources of SO4 do our tanks get?


----------

