What is the best glue for aquariums?

There are many different types of adhesives that can be used for aquariums because there are many different parts of aquariums that need glue. Let’s find out what glues are best suited for each part of your aquarium.

Table of Contents

Bestseller No. 1
RA AquaTech Aquarium Glue Clear for Plants Corals aquascaping Instant Aquarium Safe (4pcs Pack)
  • Note: For aquarium live plants, corals, small artificial decoration or small rocks. If you need to glue large decoration or rock, use silicone instead.
  • Note: Unlike some adhesives that cure by evaporation or heat, this cyanoacrylate is aquarium-safe stable formula that needs moisture to cure. If applied in a dry environment, spray some water to expedite the curing process. If an excess amount of glue is exposed to air without sufficient moisture, it will not cure properly.
  • For the best result, always apply the glue directly to the point of contact between surfaces not "around" it. Depends on the moisture level and the amount of glue used, the fixture time varies from 10second to 30mins, full cure time varies from 10mins to 24 hours. You don't have to wait! Once it cured to partial strength, place it in your aquarium and let it fully cure underwater.
  • Superior cyanoacrylate gel, extremely thick formula. Works underwater or above water. Insoluble in water, 100% safe for freshwater, saltwater aquariums & reptile (heat resistant up to 150F)
  • 5grams each tube, total 20grams per pack. Small individual package, increase utilization rate.
Bestseller No. 2
Seachem Flourish Glue
  • Performance driven at affordable prices
  • Made in the USA with quality materials
  • Field tested to ensure nothing but the best for your pet
  • Bonds within seconds
Bestseller No. 3
Aquarium Glue,2 pcs Safe and quick-drying aquascape water plant glue for Corals aquascaping Instant glue for plants, moss, coral, stone, wood,coral, non-toxic, fresh and salt water-multiple color
  • 【The best choice in the industry】We specialize in R&D and production of aquarium glue, so our aquarium glue is at the leading level in the world. We are the source factory, refuse to increase production costs for customers because of advertising and middlemen,so our glue is cheaper but better. Many large glue sellers' glues are produced by us, we support OEM, our aquarium glue will be your best choice!
  • 【Wide application】Aquarium glue, Aquarium safe glue, Coral glue, live plant glue- Clear, for Artificial ornamental decoration, sinking woods, coral frags, stone, pottery, wood, leather, metal, moss, plastic. Unique sticky coral function available underwater. Clear aquarium glue can be perfectly integrated into all the landscapes of your fish tank and aquarium.
  • 【Safe and non-toxic】We insist on the production of exclusive aquarium glue formula, which has passed MSDS and various safety reports. Our glue is completely harmless to your fish, water plant, coral. Our aquarium glue is clear, odorless and environmentally friendly products , 100% safe for freshwater & saltwater aquariums. Many other aquarium glues are just called aquarium glues, but the ingredients are just ordinary glues, which will cause undetectable damage to your fish and water plants!
  • 【Super viscosity】 Unique instant bonding performance, which can bond any aquarium landscaping materials such as corals, moss, stones, etc. within a few seconds. If you want to make your aquarium or fish tank a perfect artwork, This is the most effective and economical adhesive. Other glues are only short-lived or even non-sticky,but our aquarium glue can always remain viscous in the water to make your aquascape stable and beautiful.
  • 【What You'll Get】2Pcs(5g per tube)Clear Safe and Quick-drying aquascape water plant glue and Lifetime Technical Support, backed by 24/7 friendly customer service. The unique glue packaging makes your use easier. The new packaging will not allow the glue to stick to your hands. When you have not finished using the glue, it will be easier to store your glue for next use. Upgraded packaging is easier to use and store!
Bestseller No. 4
Seachem Reef Glue Cyanoacrylate Gel Coral Frag Mounting, 20g Each (3 Pack)
  • 3 Pack Of Seachem Reef Glue Cyanoacrylate Gel Coral Frag Mounting, 20g Each
  • Mount coral frags and colonies to reef rock and plugs.
  • Bonds within seconds even underwater.
  • New formula is 17x thicker allowing for more control and less mess.
Bestseller No. 5
RA AquaTech Aquarium Glue Green for Plants Moss Aquascaping Instant Aquarium Safe
  • Superior cyanoacrylate gel, extremely thick formula. Insoluble in water, 100% safe for freshwater & saltwater aquariums.
  • 5 grams each tube, total 20 grams per pack. Small individual package, increase utilization rate.
  • Natural green color best for plant, moss tanks.
  • Bonds within seconds, excellent hold & durability.
  • Works underwater or above water
In general, when it comes to the outer glass of an aquarium, silicone-based adhesives tend to work the best. But not all silicone-based adhesives are created equal and some aren’t aquarium safe at all, others might be good for freshwater but not saltwater, or vice versa. Because of those reasons, the best glue for the outside glass of an aquarium is Aqueon Silicone Sealant. Aqueon Silicone Sealant is permanent, watertight, clear after it dries, doesn’t crack, is non-toxic, and is suitable for both fresh and saltwater aquariums.

Best Glue for Underwater

It can be difficult to find the best glue for underwater aquarium applications, especially if you have a situation where you need to glue a plant or a rock but can’t remove the water from your aquarium. There are many non-toxic waterproof adhesives, but few that can actually bond underwater. That is why the best underwater aquarium adhesive is Seachem Reef Glue because it can be applied to both dry and wet surfaces and it will still form its bond within a few seconds. It also works for both freshwater and saltwater, so no matter what you need it for, Seachem Reef Glue has got you and your aquarium covered.

How to Glue Aquarium Plants

Best Underwater Epoxy

An epoxy is not the most obvious choice when gluing an aquarium, but it is a very good choice as it doesn’t cause any cloudiness within the tank. A great underwater epoxy is the Two Little Fishes Aquastick Coralline because it can handle just about any kind of application in or on an aquarium.

Best Aquarium Cement

Cements are generally only used for larger aquariums as they can withstand a great amount of water pressure either through containers, sumps, or building tanks. Generally, the type of cement used for those applications is acrylic cement and the best one for an aquarium would be IPS Weld-On 16. Its gel consistency makes it easy to control, it has a fast cure time, and it has an incredibly strong bond. It’s perfect for and heavy-duty tanks.
To summarize, the best overall glue for aquariums is Aqueon Silicone Sealant. The best underwater glue is Seachem Reef Glue. The best underwater epoxy is Aquastick Coralline Red. And the best acrylic cement is IPS Weld-On 16.
It very much depends on the glue. Some would be toxic to the plants and animals inside the aquariums, but all the ones recommended in this article, if used in the ways we recommended them, are perfectly safe for aquariums.
When using the Aquastick Coralline Red, just like with any epoxy putty, get a bit in your hand and play around with it to warm it up to room temperature before placing it into the desired surfaces and leaving to cure for 12 hours.
Yes, Aqueon Silicone Sealant could definitely be used to affix decorations to a tank. Just make sure it gets the appropriate cure time of 24-48 hours.
Yes, IPS Weld-On 16 is very much toxic as it contains solvents and it should never be used on the inside of a tank for fear of poisoning the wildlife inside.
Yes, Seachem Reef Glue adheres to glass so you can glue things directly to the tank should you wish to do so.
Woman using a gluestick
Woman using a gluestick

Looking for the best glue for aquariums?