Does flourish excel have potassium in it?

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JackBlasto

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My planted aquarium is testing pretty high in potassium. I dose Flourish excel daily and that's about it so I was wondering if it contained potassium and thus would be contributing to the reading or if it was something else. I will quit dosing excel if it is but want to continue if it's not the excel causing it. Anyone know? I tried google and it appears that excel only has something called glutaraldehyde it. I doubt this is all that's in it so was wondering if anyone knew? Thanks.
 
Good to know. Any idea why my water would have a high potassium content? Everyones tap water just different? I have read that potassium in a planted tank can take higher doses fine but that it can lead to algae. I'm not too worried about it reading high as I'm going to start adding RO water which will bring it down but I was just curious as to where it came from. I bought a test kit that indicates as high as 3ppm and mine was WAY above even that.
 
i dont think potassium will contribute to algae growth, phosphates on the other hand will. anyways the potassium is probably coming from your tap water, and yes everyones tap water is different, if you live in the US then your water supply company should have a website and on the website should be a water quality report
 
How are you testing your potassium levels? Have you tested your tap?

I agree that an excess of potassium is not going to cause algae.
 
Yeah, they are validly high. I have a hanna digital test and a liquid test to double check reading.

I've been dosing flourish nitrogen because nitrates were low. I now see 1-0-2 on the label so that means for every 1% I add to achieve some nitrate difference I am adding 2% potassium... this could make a significant amount of potassium I am adding along with my nitrogen. Any way I can add ONLY nitrate to the water?
 
What were you measuring it at?


Here's the thing though. If you're adding it at a 2:1.5 (from Seachem's site, they apparently don't know how to round) ratio to get nitrates up, the potassium will be increasing at roughly the same speed as nitrates, but you can't get your nitrates up, so I doubt that's your major potassium source.
 
Well I'm measuring it at over 100 ppm because my meter only reads up to 100 ppm and it's not reading it and giving me a too high error on the readout. To verify the meter was working correctly I tested my other smaller aquarium and that one reads at 54 ppm and I tested my tap water which reads at 0 ppm. When I do a liquid test of the same it's extremely cloudy when the regent is added so I'm believing the over 100 ppm reading is accurate. The high level might be because of the substrate I used setting up the tank called aqua dirt. I can't try to vacuum the substrate any as there is 5 months of plant growth carpeting it and I'd really mess up a lot if I tried that at this point.

Now, I guess my question is what kind of effect does this huge amount of potassium have on the plant life? I am currently doing water changes and assume that over time this will remedy itself but wondering if this is something I should be too worried about? I need to supplement KN03 because my nitrate levels are LOW and when I dose KN03 the plants immediately start to pearl so I'm fairly certain that I need to continue supplementing the tank with AT LEAST KN03 for the time being. I'm just wondering how I remedy this potassium issue or should I just relax and keep doing water changes every few days and it'll all be fine? Thanks for any advice.
 
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I still don't think your device is calibrated properly. To get a concentration of K+ of 100 ppm in a 100g tank, you would need to add about half a cup of either KNO3 or K2SO4. The fact that it measured these high levels in two tanks pretty much convinces me of this.
 
Thank you once again, Aqua Chem. I just sifted through the manual to see how to see when the device was calibrated last. It turns out it was NEVER calibrated at the factory. This means I need to find a solution called HI 96750-11 Cal Check which will allow me to calibrate it myself. Thanks for bringing this to my attention. I'll be calling Hanna instruments in the morning to discuss what they can do for me since they technically set up the instrument property.
 
With most analytical instruments, you should be calibrating them every time you use them. At the very least it should be recalibrate periodically.
 
Ok. Well I dealt with Hanna Instruments and they said that the device was calibrated at the factory, that it wasn't recalibrated AFTER that... Well, I got the calibration solution and calibrated it myself and it was off by not much, by .01 soooooooo, I check the levels of RO water and it's 0. I test my aquarium in question and it's still above 100 which is as high as the meter reads. The meter is correct. So, when dosing fertilizers WHILE I get my potassium down what would I eliminate from the following:


Potassium Nitrate KNO3
Mono Potassium Phosphate KH2PO4
Potassium Sulfate K2SO4
Magnesium Sulfate MgSO4

It makes sense to eliminate ALL of the ones with K in it, heh... so does this leave me dosing ONLY magnesium sulfate while I do water changes to get my potassium down?

This all has to be because of a substrate that I used. It is called aqua durt: Chemical makeup is as follows:

TYPICAL CHEMICAL ANALYSIS
component weight %
volatile free basis
SiO2....................................76.72
Al2O3..................................11.28
CaO......................................0.63
MgO.....................................2.04
Na2O....................................0.10
K21O....................................1.26
Fe2O2..................................6.51
MnO.....................................0.01
P2O5....................................0.11
TiO2....................................0.52
FeO....................................0.82
Loss on Ignition.................2.20

The other substrate I have in the sump is miracle mud with these listed, granted not in percentages of how much of each:

Aluminum, antimony, barium, beryllium, bismuth, boron, bromine, cadmium, calcium, cerium, cesium, chromium, chloride, cobalt, dysprosium, erbium, europium, fluorine, gadolinium, gallium, germanium, gold, hafnium, holmium, indium, iodine, iridium, iron, lanthanum, lithium, lutetium, magnesium, manganese, molybdenum, neodymium, nickel, niobium, osmium, palladium, phosphorus, platinum, potassium, praseodymium, rhodium, rubidium, ruthenium, rhenium, samarium, selenium, silicon, silver, sodium, strontium, sulfur, tantalum, tellurium, terbium, thallium, thorium, thulium, tin, titanium, tungsten, vanadium, ytterbium, yttrium, zinc, zirconium


Anyway, all that said, DO I need to be dosing any ferts with my potassium levels so high? The meter is right. I have read that having potassium levels this high isn't necessarily bad I'm just not wanting to add more to the situation.

Thanks for any insight here.
 
I would do 50% water changes until you get it into the dynamic range of the instrument, and then see if it responds appropriately to dosing. You should also be able to monitor if it's increasing on it's own (ie dose independent).
 
Thanks. I will take your advice and start doing 50% water changes. Out of curiosity, what kind of things could cause it to raise independent of dosing?
 
Substrate or rocks leeching would be the best options. Beyond that, we start looking at methodological issues.
 
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