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MasterLine Root Caps – Slow-Release Root Tabs for Aquarium Plants

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Trusted by 500+ aquascapers

€15,94
  • Feeds roots for 3–4 months
  • Turns plain gravel into fertile ground
  • Nutrients stay out of the water column
  • Ideal for crypts and swords
  • Safe for shrimp, fish and snails

Slow-release capsules you push into the substrate, right under the roots. They feed heavy root feeders like Echinodorus and Cryptocoryne for 3–4 months without touching your water column, so plain gravel or sand starts behaving like a nutrient-rich soil.

Size

Fast delivery (1–5 days EU)

Carefully packed and protected

Tips from real aquascapers

Description

MasterLine Root Caps — Slow-Release Root Fertilizer for Aquarium Plants

MasterLine Root Caps are slow-release fertilizer capsules that feed aquarium plants directly through their root system. Each capsule contains a complete blend of macro and micro nutrients, released gradually over 3–4 months, without affecting water column parameters.

What do MasterLine Root Caps do?

They turn an inert or nutrient-depleted substrate into a living, nutritious growing base. This makes them especially effective for heavy root feeders like Echinodorus, Cryptocoryne, and Amazon Sword — plants that struggle in plain gravel or sand.

Nutrient content (per capsule)

Nitrogen (N) 15.99%
Phosphorus (P) 3.9%
Potassium (K) 10%
Magnesium (Mg) 1.2%
Iron (Fe) 0.45%
Manganese (Mn) 0.06%
Zinc (Zn) 0.015%
Boron (B) 0.02%
Copper (Cu) 0.05%
Molybdenum (Mo) 0.02%

The nitrogen is delivered in ammonium form — the type of nitrogen plant roots absorb most efficiently, without leaching into the water and feeding algae.

How to use MasterLine Root Caps

  • Insert one capsule per 10–15 cm of substrate area, using tweezers.
  • Push the capsule deep under the root zone of the plant, not near the surface.
  • Works in both aquasoil and inert substrates (gravel, sand).
  • Replace capsules approximately every 4 months, or when plant growth slows.

Is it safe for shrimp and fish?

Yes. MasterLine Root Caps are safe for fish, shrimp, snails, and all other aquarium livestock. The copper content is minimal and does not pose a risk to invertebrates when used as directed.

Which aquariums is this fertilizer for?

Planted freshwater aquariums using soil, aquasoil, gravel, or sand substrate. Ideal for aquascapes with demanding root-feeding plants, and for reviving old, nutrient-exhausted substrates without a full substrate replacement.

Available sizes

10 pcs, 60 pcs, and 125 pcs — choose based on tank size and number of root-feeding plants.

Brand: MasterLine (Romania)  |  Category: Root Fertilizer Capsules  |  Type: Slow-release solid fertilizer

  • 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
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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.