---
product_id: 232920710
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: "R123"
currency: ZAR
in_stock: true
reviews_count: 8
category: "Wacker"
url: https://www.desertcart.co.za/products/232920710-wacker-121-professional-aquarium-fish-tank-silicone-sealant-small-to
store_origin: ZA
region: South Africa
---

# 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:** R123
**Availability:** ✅ In Stock

## Summary

> 🐟 Seal the deal with Wacker 121 — where strength meets safety in every drop!

## 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?** R123 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/232920710-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

- • **Crystal Clear Finish:** Transparent sealant that blends seamlessly with glass and stone for a flawless, professional look.
- • **Aquarium-Safe & Non-Toxic:** FDA-approved formula ensures zero harm to your aquatic life, keeping your ecosystem thriving.
- • **Versatile Industrial Grade:** Perfect for small to large tanks, glazing, and industrial bonding—trusted by pros worldwide.
- • **Fast Curing & Easy Application:** High viscosity paste applies smoothly and cures quickly, saving you time and hassle.
- • **Unmatched Strength & Durability:** Withstands extreme aquarium sizes and water pressure for a lifetime of secure bonding.

## Overview

Wacker 121 Professional Aquarium Silicone Sealant is a premium-grade, FDA-approved, clear silicone designed for strong, waterproof bonding and gap filling in aquarium tanks of all sizes. Made in Germany and trusted by professionals for over 20 years, it offers superior tensile strength (360 lbs), fast curing, and long-lasting resistance to cracking and yellowing, ensuring a safe, durable, and visually seamless seal that protects aquatic life.

## 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: Best Aquarium Grade Silicon! - This is high quality made in Germany aquarium grade silicon (Not all silicon companies state this but this one does) It is a lot thicker than Dowsil and others that I have used in the past which made it difficult to inject it in between the glass panes so I had to return the second one. Even then this is by far the best silicon available in desertcart.in for aquariums. EDIT: Aug 2022. Purchased this again and built a large aquarium using silicon injection method. This time the project was smooth. This is a very high quality "Aquarium grade" silicon. Best available in India for sure. Mind you it is a bit harder to work with as it dries faster and is thicker than the popular Dowsil silicon. Very happy with the results. Will definitely use it again if I ever build another fish tank.
Review: Good things for experienced person - It is a high quality adhesive for skilled professional and very good to use for high quality work

## 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 | #1,961 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #13 in Silicone Adhesives |
| Brand | Wacker |
| Brand Name | Wacker |
| Colour | Clear/Transparent |
| Compatible Material | Glass, Stone |
| Container Type | Tube |
| Country of Publication | India |
| Customer Reviews | 4.3 out of 5 stars 407 Reviews |
| Importer Contact Information | Wacker Chemie |
| Included Components | Nozzle |
| Item Form | Paste |
| Item Package Quantity | 1 |
| Item Type Name | Aquarium Silicone Sealant |
| Item Weight | 420 Grams |
| Manufacturer | Wacker, Wacker |
| Manufacturer Contact Information | Wacker |
| Manufacturer Part Number | WCK121 |
| Material | Silicone |
| Material Type | Silicone |
| Model | WCK121 |
| Other Special Features of the Product | Non Toxic, Strong |
| Packer Contact Information | Authorized Seller Taj Products, sellerplywoodproducts@gmail.com |
| Special Feature | Non Toxic, Strong |
| Specific Uses For Product | Glazing, Industrial Bonding Applications, Aquarium Tank Construction |
| Tensile Strength | 360 Pounds |
| Unit Count | 310 Milliliters |
| Viscosity Level | High |
| Volume | 310 Millilitres |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Wacker
- **Item Form:** Paste
- **Material:** Silicone
- **Special Feature:** Non Toxic, Strong
- **Specific Uses For Product:** Glazing, Industrial Bonding Applications, Aquarium Tank Construction

## 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)

## Questions & Answers

**Q: Does it suitable for 24"×10"×12". But Using 6mm glass??**
A: Yes, Suitable

**Q: Does it become solid or elastic after applied?**
A: Solid

**Q: Delivery charge havi I want to 121 Aquarium sealant is six names place Chang the delivery charge**
A: Not possible.

**Q: Does it comes with application gun?**
A: We have added the listing that contains applicator gun

## Customer Reviews

### ⭐⭐⭐⭐⭐ Best Aquarium Grade Silicon!
*by V***D on 13 May 2021*

This is high quality made in Germany aquarium grade silicon (Not all silicon companies state this but this one does) It is a lot thicker than Dowsil and others that I have used in the past which made it difficult to inject it in between the glass panes so I had to return the second one. Even then this is by far the best silicon available in Amazon.in for aquariums. EDIT: Aug 2022. Purchased this again and built a large aquarium using silicon injection method. This time the project was smooth. This is a very high quality "Aquarium grade" silicon. Best available in India for sure. Mind you it is a bit harder to work with as it dries faster and is thicker than the popular Dowsil silicon. Very happy with the results. Will definitely use it again if I ever build another fish tank.

### ⭐⭐⭐⭐⭐ Good things for experienced person
*by S***S on 12 August 2026*

It is a high quality adhesive for skilled professional and very good to use for high quality work

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

“i build 4 feet height 2 feet lenggt tank. The gum is super strong, but it’s very hard to use. It dries very fast—within about 10 minutes it starts getting hard—but once set, the gum is very strong.”

## 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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*Product available on Desertcart South Africa*
*Store origin: ZA*
*Last updated: 2026-08-21*