---
product_id: 725604801
title: "Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear)"
brand: "wacker"
price: "€ 25.92"
currency: EUR
in_stock: true
reviews_count: 5
category: "Wacker"
url: https://www.desertcart.fi/products/725604801-wacker-121-professional-aquarium-fish-tank-silicone-sealant-small-to
store_origin: FI
region: Finland
---

# FDA approved, fish-safe formula 100% waterproof & water resistant 360 lbs tensile strength Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear)

**Brand:** wacker
**Price:** € 25.92
**Availability:** ✅ In Stock

## Summary

> 🐟 Seal your aquarium like a pro—strong, safe, and sleek!

## Quick Answers

- **What is this?** Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear) by wacker
- **How much does it cost?** € 25.92 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.fi](https://www.desertcart.fi/products/725604801-wacker-121-professional-aquarium-fish-tank-silicone-sealant-small-to)

## Best For

- wacker enthusiasts

## Why This Product

- Trusted wacker brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Versatile Application:** Ideal for glass, plastics, ceramics, and more—seals gaps and repairs with precision.
- • **Fast Curing & Odorless:** Smooth, easy application with quick drying time and no unpleasant smells.
- • **Fish-Friendly & Non-Toxic:** FDA-approved sealant that guarantees a safe environment for your aquatic life.
- • **Long-Lasting Waterproof Seal:** Resists cracking, shrinking, and yellowing even under constant water pressure.
- • **Unmatched Aquarium Bonding Power:** Engineered in Germany for superior strength and durability, perfect for tanks of all sizes.

## Overview

Wacker 121 is a premium-grade, German-engineered silicone sealant designed specifically for aquarium construction and repair. With a tensile strength of 360 pounds and FDA approval for aquatic safety, it delivers a durable, waterproof, and odorless seal that withstands extreme water pressure and environmental stress. Trusted by professionals for over 20 years, it ensures a flawless, long-lasting bond for both freshwater and saltwater tanks.

## Description

For over two decades, aquarium professionals have trusted Wacker 121 to securely seal monster-sized aquarium glasses. This high-performance silicone sealant provides unbeatable adhesion, ensuring a watertight and durable bond for large custom aquariums. Ideal for both freshwater and saltwater setups, Wacker 121 is formulated to resist cracking, shrinking, and yellowing over time, even under constant water pressure. - *Superior Strength:* Designed to withstand extreme aquarium sizes and volumes. - *Reliable & Long-lasting:* Decades of proven use in professional aquarium setups. - *Safe for Aquatic Life:* Non-toxic, fully aquarium-safe once cured. - *Easy Application:* Smooth application for clean, precise seals.

Review: Ideal for aquarium
Review: Best silicon ever in the market, for aquarium.

## Features

- ✔️ PREMIUM GRADE ---> Made in Germany, Wacker 121 is a high performance silicone sealant designed for strong Bonding, Gap Filling & Repair of aquarium tanks, fish tanks and other glazing applications. Suitable for small to large size tank construction.
- ✔️ FDA APPROVED ---> FDA approved for fish and other aquatic animals. No toxins in it, safe and fish friendly.
- ✔️ FEATURES & BENEFITS ---> Excellent Long-term water resistance *★* Suitable for glass, plastics, ceramic products, and more *★* High strength, high toughness, high viscosity *★* Fast curing speed *★* Suitable for objects under water pressure *★* Excellent mechanical properties *★* Usage for wide variety of Glazing & Industrial applications
- ✔️ ENVIRONMENTAL ✔️ ODORLESS ✔️ WATERPROOF ✔️ HIGH-QUALITY

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B08KGVHJJ8 |
| Best Sellers Rank | #76,092 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #179 in Silicone Sealers |
| Brand | Wacker |
| Brand Name | Wacker |
| Color | Clear/Transparent |
| Colour | Clear/Transparent |
| Compatible Material | Glass |
| Container Type | Tube |
| Customer Reviews | 4.3 out of 5 stars 348 Reviews |
| Item Form | Paste |
| Item Package Quantity | 1 |
| Item Weight | 420 Grams |
| Item form | Paste |
| Item package quantity | 1 |
| Manufacturer | Wacker |
| Material | Silicone |
| Material Type | Silicone |
| Model | WCK121 |
| Other Special Features of the Product | Non Toxic, Strong |
| Special features | Non Toxic, Strong |
| Tensile Strength | 360 Pounds |
| Unit Count | 310 Milliliters |
| Viscosity | High |
| Volume | 310 Milliliters |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Wacker
- **Colour:** Clear/Transparent
- **Item form:** Paste
- **Material:** Silicone
- **Special features:** Non Toxic, Strong

## Images

![Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear) - Image 1](https://m.media-amazon.com/images/I/410-A9QCDCL.jpg)
![Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear) - Image 2](https://m.media-amazon.com/images/I/51-7mLb8NQL.jpg)
![Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear) - Image 3](https://m.media-amazon.com/images/I/613gvPZhUCL.jpg)
![Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear) - Image 4](https://m.media-amazon.com/images/I/618rQczFfsL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Ideal for aquarium
*by P***S on 26 December 2025*



### ⭐⭐⭐⭐⭐ Best silicon ever in the market, for aquarium.
*by A***Q on 7 March 2024*



### ⭐⭐⭐⭐ Good quality
*by H***H on 31 January 2026*



## Frequently Bought Together

- Wacker 121 Professional Aquarium, Fish Tank Silicone Sealant | Small to Large Tanks | Bonding, Gap Filling & Repair | Safe for Fish (310ml - Clear)
- BIONIX Freshwater Master Test Kit (200 Test).

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**Shop now:** [https://www.desertcart.fi/products/725604801-wacker-121-professional-aquarium-fish-tank-silicone-sealant-small-to](https://www.desertcart.fi/products/725604801-wacker-121-professional-aquarium-fish-tank-silicone-sealant-small-to)

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*Product available on Desertcart Finland*
*Store origin: FI*
*Last updated: 2026-03-02*