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Potassium Nitrate (KNO3) Aquarium Fertilizer - 1lb Jar

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Potassium Nitrate (KNO3) Aquarium Fertilizer - 1lb Jar
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Potassium Nitrate KNO3 - Aquarium Plant Food

  • 1lb/Jar
  • provides Nitrogen (N) and Potassium (K) to aquarium plants. Macronutrients essential for healthy plant growth and survival.
  • Want the world's best KNO3? Our 1lb jar of Potassium Nitrate, is the finest quality and purity aquarium plant food to make your aquascape a success.
  • Nitrogen (N) is essential for chlorophyll production. Potassium (K) aids protein synthesis and for plants to metabolize Iron (Fe). Nitrogen is an essential component of chlorophyll, the green plant pigment responsible for photosynthesis. Nitrogen is vital to all living cells and is a necessary part of all proteins, enzymes and metabolic processes of energy synthesis and transfer. Nitrogen helps plants with rapid plant growth and healthy leaf quality. Nitrogen deficiency creates an imbalance in plants, resulting in stunted and slow growth rate, chlorosis (yellowing of older leaves), die off of older leaves, and new leaves are small and crippled. Potassium deficiency causes holes on older leaves. To remedy Nitrogen deficiency, increase the levels of available Potassium Nitrate (KNO3). Aquatic plants absorb nitrogen from nitrates (NO3). Ideal source of nitrates (NO3) is Potassium Nitrate (KNO3).
  • aids in chlorophyll, photosynthesis, proteins, enzymes, nucleic acids, amino acids, potassium absorption, metabolism, rapid growth and leaf quality

Deficiency Symptoms: interveinal chlorosis of older leaves, crippled new leaves, slow/stopped plant growth

Guaranteed Analysis:

  • KNO3 13.7-0-46
  • Total Nitrogen(N) - 13.7%
  • 13.7% Nitrate Nitrogen
  • Soluble Potash(K2O) - 46%

How to dose Potassium Nitrate KNO3 in your planted aquarium

Learn everything you need to know about aquarium plant fertilizer, plant nutrients, optimal nutrient levels, and diy fertilizer dosing methods: Dry Fertilizer Calculator and Fertilizing Methods

Expect an increase of 1ppm NO3 per every 62 milligrams (equivalent to less than 1/64 tsp) KNO3 added to your 10gal aquarium to yield:

  • NO3 1ppm
  • N 0.23ppm
  • K 0.63ppm

Customer Reviews

9 reviews

  • 5

    GLA Ferts

    Posted by Drew on 17th Mar 2023

    I have used GLA ferts (I dose EI) for years and they are excellent! Just now had to restock because the powder lasts forever! Trust GLA!

  • 5

    Its perfect if your looking for pure Kno3.

    Posted by Dwayne Silverman on 4th Mar 2022

    If your looking for 1lb of Kno3 for pennies on the dollar this is it. I used the elementary calculator they had and I easily made my own DIY recipe. Piece of cake!

  • 5


    Posted by Bobby on 3rd Mar 2022

    The best kno3 I have ever used and coming from me with only half a brain this says a lot!

  • 5


    Posted by Unknown on 18th Feb 2022

    Excellent value. Great results with EI dosing regimen.

  • 5

    Did a good job of bring up Nitrates

    Posted by Dave D on 10th Sep 2021

    Due to excessive plant mass relative to bioload, I was getting algae in the presence of low nitrates. I needed some fertilizer salts to raise my nitrates. This worked great to hit the target range on my aquarium.

  • 5

    Working wonders for my Reef!

    Posted by Scott on 20th Jan 2020

    I dont have a planted tank but I do keep reef tanks and word is out that GLA carries the best pure Nitrate for reef tanks around. I gave this stuff a try and the results have been amazing. I mix 1 teaspoon to 100ml RO/DI. I dose 5ml in my tank raising my nitrates to about 3.5ppm. If your looking to raise Nitrates in your reef tank this is absolutely the stuff to use. Thanks GLA for providing excellent salts for my reef. I also use Kh2po4 in my reef and the results are equally as rewarding.

  • 5


    Posted by Luke on 20th Jun 2019

    The jars were exactly what was looking for

  • 5

    Great for establishing no3 in ULN reef systems

    Posted by Dustin Pecoraro on 5th Mar 2019

    This product worked great... mixed 45 grams of powder with 500ml of ro/di water. I had zero no3 in water and po4 was around .06 I was dosing 15ml. In my 300 gallon frag sustem morning and night until I got around 2-3 no3. It also lowered my po4 to about .04 for a few days, if the kno3 had anything to do with that, Maybe... Product worked great and corals look nice... Plus, I have enough to last 5 years... lol... don’t hesitate buying if you have a ULN system... It will get you where you need to be

  • 5

    Reliable Macro Fertilizer

    Posted by Jose Camacho on 7th Feb 2019

    I have been using this product for years now. It used to come in a zip-loc bag but now with it's own container it looks really nice. Not only is it affordable, but it makes a great improvement to any planted tank. Highly recommend it.

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