Aquarium Safe Super Glue

Aquarium Safe Super Glue: What Is It And How To Use It

Perhaps the most common reason why people buy aquarium glue is to keep plants in place. This is understandable because aquarium plants are usually planted for aesthetics and since they are fully immersed in water, they do not usually stay in place. The easiest and most permanent way of making them stay in place and grow to improve the aesthetics of your tank is to use aquarium glue; not strings or weights.

Not all glues on the market are safe for use in aquariums. Most of them are pretty toxic, to be honest. This is why you should strictly use aquarium-safe glue. 

In this post, I will share with you everything you need to know about aquarium-safe glue and the best aquarium-safe glue products on the market.

What is An Aquarium-Safe Glue?

When you search online for an aquarium-safe glue, you will find dozens of products. However, not all of them will be completely tank-friendly. In other words, not all of them will be 100% aquarium-safe glue products. 

Below are the properties of a 100% aquarium-safe glue product:

  1. It can withstand water

Many glue products claim to be aquarium-safe but they are not because they cannot withstand water. Therefore, before you buy any aquarium-safe glue product, you should check if it can work underwater. 

  1. It is inert when wet

Several glue products on the market do not become inert when wet. You should, therefore, avoid them like plague as they are not aquarium-safe. Aquarium-safe glue products become inert when wet. In other words, they become chemically inactive when wet.

This means they last long underwater and do not release any chemicals.

  1. It does not cloud tanks

Some people report clouding when they utilize certain glue products. This is not right. If you use a glue product and it causes clouding, you should throw it out immediately. This is because the clouding will mean it is releasing chemicals and that is not right.

The best aquarium super glues do not release any chemicals and, therefore, do not cause clouding.

Types of Aquarium-Safe Glue Products

There are three main types of glue products that can be used to keep things in place underwater, to fix leaks and for general tank maintenance. They are Super Glue products, Silicone products, and Epoxy products.

  1. Super glue products

Super glue products are the best adhesives for anchoring plants. This is because they are typically the strongest. There are many aquarium-safe super glue products on the market. The best ones are cyanoacrylate-based. 

The advantages of super glue products include the fact that they are inexpensive, a breeze to use, and effective/ long-lasting. 

  1. Silicone products

Silicone adhesives are the best adhesives for fixing tank cracks and sticking ornaments. There are many aquarium-safe silicone adhesive products on the market, and most of them are very effective.

The advantages of silicone adhesive products include fast drying, flexibility, multiple color options, and compatibility with glass. Most silicone adhesives also do not release any chemicals so they are very safe for fish.

  1. Epoxy products

Epoxy is not really glue in the traditional sense of the word. However, it is a really good adhesive, especially for aquarium maintenance. This is because it allows materials to dry in water. 

Epoxy is perfect for repairing liking pipes, repairing underwater equipment, bonding rocks, and carrying out general fish tank maintenance.

You now know what an aquarium-safe glue is and the types of aquarium-safe glue products on the market. It is time to discover the best aquarium-safe glue products on the market. 

The 5 Best Aquarium-Safe Glue Products

Below are the top five aquarium-safe glue products. They are all safe for fish and plants. They can be used to attach plants or for general fish tank maintenance. 

  1. MARINELAND Silicone Squeeze Tube

This is a special silicone aquarium-safe glue. It is made by MarineLand – a reputable manufacturer that is renowned for making high-quality aquarium products including tanks and filters.

The best thing about this glue is the fact that is caulking silicone and hence it can be used to fix broken ornaments and glass cracks. Most aquarium-safe glue products on the market are made to hold stuff in place. In contrast, this one is strong enough to join things together and hold them together. 

The second best thing about this silicone aquarium glue is the fact that it is relatively cheap compared to other aquarium-safe glues on the market. 

Lastly, this silicone glue makes repaired glass look like new. So if you want to repair your broken tank or a glass ornament, you should use it if you don’t want anyone to know about it.


  • This is an amazing an aquarium-safe glue
  • It is caulking silicone perfect for fixing glass cracks 
  • It is relatively cheap compared to other silicone glue products
  • It makes repaired glass look like new


  • It is not very good for holding decorations in place
  1. Seachem Reef Glue Cyanoacrylate Gel

This product has the Amazon’s Choice label. This means it is a high-rated product that is well-priced. The reason why this product is highly-rated is the fact that it is one of the best super glues on the market.

It is a cyanoacrylate super glue that is absolutely brilliant for bonding things underwater.

The thing I love the most about this Seachem glue is the fact that it is not messy at all; it is really flexible because it is made of cyanoacrylate. This makes it a breeze to apply especially on plant roots. 

I also love the fact that this glue is thicker and stronger than other super glues. The thickness does not affect its finish at all. It almost always looks nice and clean.

Lastly, I like the fact that this Seachem glue can be used to fix just about anything


  • This is an Amazon’s Choice product
  • It is perfect for planting aquatic plants
  • It is great for fixing things underwater
  • It is ideal for general tank maintenance


  • It dries up quickly in the tube once you start using it
  1. Aquastick Coralline Red

This is a brilliant epoxy-based adhesive that is perfect for various uses. It is well-rated on Amazon and other online e-commerce stores.

What stands out the most about this epoxy adhesive is that it can be used to stick just about anything together underwater. Its best use is the fact that it can be used to strongly bind rocks together. Other types of aquarium glues cannot be used to bind rocks together since they do not work really well on rocks.

What also stands out about this epoxy glue is that it hardens very quickly. This makes it perfect for securing plants and ornaments quickly. 

This aquarium-safe epoxy glue is also very easy to use. This is because it is stick-free; it won’t stick any two things together unless you deliberately want it to.


  • This is a well-rated epoxy glue 
  • It can be used to stick rocks, plants, and ornaments
  • It is very easy to use
  • It is not messy


  • It is not great for fixing glass cracks
  1. SILA-SEAL Clear Professional Grade

This is a professional-grade silicone glue that is made in the USA. 

What won me over about it is the fact that it is quite tough and flexible at the same time. It cures into a solid rubber-like material after a couple of minutes. This makes it hold stuff together more effectively than other glues.

I also like the fact that it is long-lasting. In laboratory conditions, it has been shown to last long and bind materials firmly together even when exposed to high temperatures.

Lastly, I like the fact that it is extremely safe. It has a certification which means that once it is cured, it cannot even contaminate human food. Therefore, when you use it to hold things together in your tank, you won’t have to worry about it affecting your plants or fish.


  • It is a professional-grade glue
  • It is tough and flexible 
  • It is long-lasting
  • It is 100% aquarium-safe


  • It has to be bought as a case of 12 (which is relatively costly)
  1. Clear Aquarium Silicone Sealant

This silicone sealant from ASIA is one of the best aquarium-safe glues in my opinion. There is nothing not to like about it. 

First, it is strong. It does not break easily.

Second, it is not toxic for fish as it is specifically designed for aquariums.

Third, it does not slump and is, therefore, applicable to vertical surfaces. You can literally use it to fix anything.

Lastly, it can withstand a wide temperature range.



  • It is perfect for maintenance
  • It is perfect for fixing cracked glass


  • Not great for acrylic tanks


An aquarium safe glue is a ‘glue’ product (could be super glue, silicone, or epoxy-based) that is safe for use in aquariums. In other words, it is not toxic to fish and plants. Different aquarium-safe glue products are great for different uses including fixing cracked glass, anchoring plants, binding rocks, and general tank maintenance. In my opinion, among the five best aquarium-safe adhesives reviewed above, the best one is the Seachem Reef Glue Cyanoacrylate Gel (number 2 on the list above).