Aquarium Glue – Adhesives That Are Suitable for Fish Tanks
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Aquariums are wondrous things, full of exciting fish that provide stimulation for the eyes as they swish and swirl around the tank, ducking under the rocks and twisting through the plants. Perhaps you prefer the typical fresh-water aquarium, or maybe you would like to go the extra mile and create an oceanic aquarium filled with clownfish and sea anemones. Regardless, your fish tank will be nothing without the appropriate aquarium glue. Aquarium-safe glue works wonders to keep the water from leaking, and the fish will be glad for it! Today’s topic will discuss the best fish tank glue and the best glue for aquarium plants that is not toxic. We will talk about the pros and cons of using superglue for aquarium purposes, as well as whether or not hot glue is aquarium safe. If you are about to build your dream aquarium, or maybe you want to fix up an old one that leaks, keep reading! By the end of this tutorial, you should know all there is to know about aquarium-safe adhesives.
Table of Contents
Suitable Adhesives to Use in Aquariums
There are so many glue variants available to choose from and the decision can be an intimidating one to make! You might be w For your benefit (and the benefit of your fish), we have put together a list of the most suitable aquarium-safe glues.
Aquarium Cement Glue
A tank is super bland without bits of coral, rocks, and possibly a pirate shipwreck for the fish to swim around. This means that you need the best glue for aquarium plants so that the water remains free of toxins. Thus, whatever you are gluing will stay intact even though it is submerged underwater.
Whether your aquarium is massive or massively small, this is the perfect glue to build the best obstacle course for your fish. Maybe you want to glue a mermaid to a rock – the choice is yours. This glue has been recommended by many professionals and it has high tensile strength.
More often than not, this type of glue is used for bonding pipes that are made of PVC. This makes it a versatile adhesive as it can glue different materials and when it has dried, it can handle being submerged underwater as well.
How does aquarium cement work? Not in the way that you might think. It does not simply glue two surfaces together; it fuses them. The molecules bond together, making it the strong adhesive for which it has been recognized as.
There are various types of aquarium cement glues. One type of aquarium cement has a watery consistency and is viscous. This is used for bonding sheets. The second aquarium cement variation is much thicker and it should only be completely dry before any water is added into the tank. If you want to glue the walls of your aquarium together, you can use this glue because it will hold the structure together perfectly.
Aquarium Super Glue
Superglue has become one of those go-to adhesives that we use for pretty much any kind of repair. From gluing ceramic mugs back together to fixing your fish tank, or even building one from scratch, this glue is ideal for almost all your projects. For the aquarium industry, super glue is one that you simply cannot do without. If you are using super glue for your aquarium, you are most likely using it for the rocks that you are sticking together, or maybe as the glue for aquarium plants, because those will occasionally need some adjusting.
Superglue makes for an aquarium-safe adhesive, but you need to make sure that the glue does not have any additives because those are what contaminate the water. Needless to say, this means that not all superglue variations will be suitable for aquariums. An example of aquarium-safe super glue would be ethyl cyanoacrylate, so keep an eye out for this one when you are at your local hardware store or aquarium supply store.
An interesting fact is that the method of securing your rocks, plants, or other decorative fixtures to your fish tank is called fragging. This method calls for glue that has a gel consistency, and this means that the superglue should also have the same consistency. The gel-like glue makes it easier to hold things in place whilst the curing happens. The more watery glues will make it hard for the fragging because all the items you are gluing will slip around and possibly cure in the wrong position.
Silicone Glue for Aquariums
Silicone might have already crossed some of your minds, and this is understandable because it feels like it would be an aquarium-safe adhesive. Silicone is a fast-acting adhesive, which means you can use it for those emergency fixes in your tank. You might have noticed a slight leak in the one panel, and the silicone can easily fill up the hole and stop the water from coming out. You could use this glue as a preventative for the same cause, preventing the water from leaking through the corners of the tank.
Glass and plastics are not an easy materials to glue. Having sheer and non-porous textures, most glues simply slide off. Silicone works wonders where other glues cannot in terms of gluing the glass panels together to create the tank. It even seals it off to make it watertight. Once the water has been added to the tank, you must understand that there is a lot of pressure placed on the walls. Luckily for you, the silicone glue can handle the pressure, and your tank will be safe from bursting open.
The only downside with using silicone as an aquarium glue is that not all silicone adhesives are suitable, and if it is not pure silicone, meaning 100% silicone, then it will not work as well as it should – if it works at all.
When fixing or building aquariums with silicone glue, you have two options. The one option is metallocene, which is the better-quality selection. The second option is known as ethylene-vinyl acetate (EVA), which is much more affordable. Make sure that you read the label of both options because the manufacturers will provide a detailed list of the instructions for use as well as the ingredients used to make the glue. This is where you will see how many toxic additives are present, as well as whether the glue is or is not aquarium safe.
Hot Glue for Aquariums
Firstly, is hot glue aquarium safe? Many people have asked this question. In short, hot glue is perfectly safe for aquariums, and you will be able to use it without much effort. This is a great option for any items that will be submerged under water in the tank, as the glue will easily withstand the water it is exposed to as well as the pressure the water gives.
Hot glue is an interesting adhesive to apply. You will first need to make sure you have a hot glue gun at home or buy one from your local store. They are also quite easily found in most craft stores. If you are buying a new one, then you might be lucky enough to get one that includes the glue sticks, otherwise you can buy these separately. The glue stick is inserted into the glue gun which heats the glue to the point where it melts. You simply need to then pull the trigger and the now liquid glue can be applied to the surface to be bonded.
All of this information might seem a bit daunting, therefore, we have made a table that summarizes the efficiency of each type of glue when it comes to aquariums.
| Type of Adhesive | Is It Aquarium Safe? |
| Silicone | ✔ |
| Cement | ✔ |
| Epoxy Resin | ✘ |
| Super Glue | ✔ |
| Hot glue | ✔ |
| Thumb Tack | ✘ |
Various Uses for Aquarium Glue
This might come as a surprise, but fish tank glue is not limited to fixing just fish tanks. There is a lot that these glues can do that you might not have initially thought of. You do not only need it to glue your aquarium’s walls together to repair a leak that threatens the safety of your beloved fish. You can also use it to build the structure that the fish swim around. This means that you can be extra creative – because anything looks aesthetically pleasing with colorful fish swimming around it.
You might even have a fish pond, and there you might want to build a collection of fake rocks for the frogs to jump around. In this case, the glue would work just as well. You also will not have to use clamps to lock the items together because the glue is fast-acting.
Here is a great idea for your aquarium that will cut the cleaning time in half for sure! Instead of putting the rocks at the bottom of the tank loosely, you should rather stick them together in clumps of rocks. This will help you when you need to clean the rocks of the algae and sediment from the excrement of your fish. You will be able to take out the clumps you have made instead of having to take each rock and pebble out individually.
Recommended Aquarium Glue
For the betterment of both your aquarium and the lives of the fish that live inside, we have made a list of the adhesives that we prefer to use. The following products are all highly recommended by both professionals and hobbyists alike.
Top Pick for Cement: WELD-ON 16 Acrylic Plastic Cement
Weld-On is a reputable brand that has been making adhesives for a while now, and each product they make is made with high-strength capabilities. The Weld-On Acrylic Plastic cement glue creates a seamless effect when you use it for the walls of your tank. It dries perfectly transparently, which adds to the professional aesthetic.
It seems as if the Weld-On brand has made sure that the glue provides everything a glue of its nature should provide. This includes fast drying characteristics as well as the ability to withstand the pressure from the water when the tank is full. It is versatile with what surface materials it can glue, but most effective when you are gluing plastic or acrylic items together.
- High strength acrylic cement for cast, molded, or extruded acrylics
- Sets to touch-dry in minutes, fully cured to strong bond within hours
- Bonds acrylic plastics, styrene, butyrate, PVC, ABS, and polycarbonate
- Mostly effective for bonding plastics
- Transparent when dry
- Seamless effect
- Highly recommended brand for aquarium glue
- Easy application
- Available in most hardware stores
- Only one small size available
- Container may be difficult to reseal
Top Pick for Super Glue: GORILLA Super Glue Gel
Of course, Gorilla Glue is a part of this list, as they are one of the most well-known brands that make adhesives on the market. This is rightly so because they have been making top-notch glues for a few generations now. Their gel superglue is one of the most versatile glues in their range of adhesives suitable for aquariums. You will be glad to know that this super glue is 100% ethyl cyanoacrylate, meaning that it is entirely suitable for your fish tank and will not contaminate the water.
In addition to being the perfect glue for aquarium plants, this Gorilla Glue product is also the perfect glue for aquarium plants because of its fast-drying nature. The glue has also been designed not to run, so there will be no risk of glue dribbles ruining the clear glass tank.
- No run control gel formula that is great for use on vertical surfaces
- Gorilla tough anti-clog cap helps keep glue from drying out
- Specially formulated for increased impact resistance and strength
- The formula is thick enough to adhere to vertical surfaces
- Application is easy
- Non-toxic formula
- The curing time is quite short
- You have the option to buy a 10-pack if required
- There is only one color to choose from
- The glue must cure before it comes into contact with water
- Only available in one size
Top Pick for Silicone: GE Silicone Clear Window & Door Silicone Rubber
When it comes to aquariums, silicone is a truly special material. You will realize why it is so wondrous the moment you start gluing the sheets of glass together to create the actual tank. Due to its sheer texture, glass is often difficult to glue. However, GE has developed a glue that is more than capable of adhering to the sheer texture of glass. For this reason, it has become a necessity within the aquarium industry.
The brand is aware of the fact that a fish tank can only have pure adhesive, so the silicone would need to be 100% silicone, and nothing less. This is exactly what they have provided, so the water will not be contaminated by the additives in the glue.
- Mold-free, same-day use, rain-ready, and permanently weatherproof
- 100% silicone for interior and exterior use with lifetime guarantee
- Adheres to most wood, metal, vinyl, plaster, glass, and plastic
- Can endure harsh conditions like high heat and humidity
- Pure silicone adhesive
- Works with many different types of applications
- Meets federal standards
- Simple application with instructions included
- This glue only comes in one size
- More expensive than other glues
- There are only two color options
Top Choice for Hot Glue: SUREBONDER Mini Hot Glue Gun
This is a very affordable hot glue gun that comes equipped with 12 glue sticks, which can be used quickly and easily for repairs on your fish tank. It might end up being a temporary solution to the leak, but at least your fish will be happy in their tank that is still filled with water, and you will not have to transport them into a bowl for safekeeping.
A bonus with this mini hot glue gun by Surebonder is that there is not just one heat setting, so if you need only a small amount of glue, you can use the low setting, and if the repair requires a lot of glue, then the higher setting is better. Not only that, but there are also six inches of length with the power cord, so you are not limited in movement with this product. You will be able to move around freely and glue the tank as you see fit.
- Compact and easy to use for household tasks, repairs, and craft projects
- Adjustable temperature switch for bonding various materials
- 20-watt tool includes kickstand, 60-inch electric cord, and 12 mini glue sticks
- Works well for various applications
- Easy to use
- Easy to store
- The brand is well known and well recognized
- Worth the cost
- Only a temporary fix
- The strength of the bond may deteriorate in heat
- May not be suitable for marine tanks
Finding a Suitable Fish Tank Glue
Using superglue for aquarium repairs is not usually the first thing that comes to mind. It is a highly toxic substance and it will poison the water if you are not using the right one. Furthermore, using superglue for aquarium repairs is risky not only for the toxicity levels but also because the likelihood of the glue not working is high, in which case you will need to try another option if it is not too late.
The question remains: what makes fish tank glue safe to use? Or you may want to know what makes glue for aquarium plants safe to use? This is a very scientific question, with a very easy answer: read the label. Adhesive manufacturers will clearly state on the packaging of their product when that glue is suitable for a fish tank. This will not only be non-toxic once cured, but it will also be resistant to pressure and liquid of any kind.
The right aquarium-safe glue will have high tensile strength properties as well as be free of additives, so that there is no contaminating the water in the tank. You will appreciate it if the glue dries clear as well, otherwise, you will have huge glue marks along the edges of your tank.
Now that you have finished reading this tutorial, you should be super clued up on which aquarium glue can repair or build your beloved fish tank. Aquarium-safe glue may not be the most common glue in the adhesive industry, but it sure is one of the handiest. It is watertight and will keep your fish safe within their little water environment. Speaking of fish, you are probably reading this because there is a leak in your tank, so why not go and put this information to good use and save those fish!
Frequently Asked Questions
Which Glue Is Suitable for Aquarium Plants?
Using superglue is the best option for aquariums. Keep in mind that this glue should have absolutely no additives or preservatives that could contaminate the water.
Can I Use Hot Glue for Aquariums?
Is hot glue aquarium safe? You might be glad to know that you can indeed use hot glue in your fish tank safely. The only requirement is that there is no water in the tank because the melted hot glue is highly toxic and it will poison the water, and your fish will not dwell too nicely with that. Make sure the glue has dried fully before you even think about adding water.
Can I Apply Fish Tank Glue in Water?
Luckily for those who suddenly notice a leak in their very full fish tank, you can quickly seal it up by using the right fish tank glue. This is possible because the glue has been designed to be impervious to pressure or any kind of moisture.
