Delivery throughout the EU
1 3

MasterLine Nitrate - NO3 & Potassium Booster for Aquarium Plants

Trusted by 500+ aquascapers

€10,90
  • For pale, stunted new growth
  • 1 ml per 30 L adds about 1 ppm NO3
  • Raises nitrate without shifting other nutrients
  • Adds potassium alongside the nitrogen
  • Dose by test kit, when it is needed

Pale new growth and stunted stems while you already dose a complete fertiliser usually mean nitrate has dropped through the floor. This is the corrective bottle: 1 ml per 30 litres adds about 1 ppm NO3, so you lift nitrogen back up and leave everything else untouched.

Size

Fast delivery (1–5 days EU)

Carefully packed and protected

Tips from real aquascapers

Description

MasterLine Nitrate — Targeted NO₃ & Potassium Correction

MasterLine Nitrate is a single-element macronutrient fertilizer supplying nitrogen in nitrate form, together with potassium. Nitrogen is one of the most essential nutrients for aquatic plants, and in planted tanks it's often depleted faster than expected due to denitrification in the substrate and filter.

When you need this product

  • Nitrate readings drop below 5 ppm — a common warning sign of denitrification
  • You dose complete fertilizers but still see pale new growth or stunted stems
  • You fertilize with individual elements (dry dosing / EI method) and need precise nitrate control
  • You want to fine-tune a complete fertilizer like MasterLine All In One without over-dosing other elements

Composition (per 100 ml)

Nitrogen (N) 0.69%
Potassium (K) 1.89%

Dosing

1 ml per 30 L adds approximately 1 ppm NO₃ and 0.63 ppm K. Dose as needed based on test kit readings — this is not a fixed daily/weekly product, but a corrective one. Do not allow tank nitrate to fall below 5 ppm; note that in tanks with active denitrification, levels can drop to 0 ppm quickly.

Combine with

MasterLine Nitrate can be used alongside any single-element MasterLine fertilizer, or as a supplement to complete formulas such as All In One Golden or All In One Lean when you need extra nitrate control without adjusting the rest of your dosing routine.

Important notes

  • Do not contaminate the bottle with aquarium water
  • Keep out of reach of children and pets; do not ingest
  • Store at room temperature, protected from light, heat, and frost
  • For aquarium use only

  • Professional support

    Expert help when you need it

  • Delivery throughout the EU

    Delivery to all EU countries

  • Secure payment

    Fast and secure payment options

  • Easy returns

    Лесно връщане и замяна
​

FAQ

What makes Aquarium Boutique different from mass-market stores?

We don't sell everything — we sell only carefully selected products, personally tested. Every item is chosen with a clear purpose: to work well and last long. You don't need to guess about quality — we've already done that for you.

Do you ship to my country?

Yes, we ship across all of Europe. For Bulgaria we work with BOX NOW and Speedy — fast and reliable home or locker delivery. For other EU countries we use international courier services.

How quickly will I receive my order?

For orders within Bulgaria, we typically deliver within 1–3 business days. For other EU countries — usually 3–7 business days depending on location.

Can I return a product if I'm not satisfied?

Yes. If something doesn't meet your expectations — contact us. We have a clear and fair return policy. Your satisfaction matters to us and we will find a solution.

Do you offer advice on product selection?

Absolutely. Our team keeps aquariums and knows the products personally. Write to us — we'll help you choose the right solution for your tank, budget and experience level.

Are your products tested and approved?

Yes. Every product in our store has gone through our personal selection and testing process . We only work with trusted brands and don't list products we don't believe in.

What payment methods do you accept?

We accept all major payment methods — credit and debit cards, PayPal, and cash on delivery for Bulgaria. All payments are secure and encrypted.

How can I track my order?

After your order ships, you'll receive an email with a tracking link. You can follow the status in real time directly through the courier's website.