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The Best Aquarium Glue For Rocks!

As more and more people start to try their hand at aquascaping in their aquariums as well as adding custom rock features, we have noticed a drastic increase in the number of people reaching out and asking for advice on using aquarium glue for rocks.

Unfortunately, most of the glue products on the market are simply not safe for use in an aquarium either due to containing toxic ingredients or being water-based and not working in water.

Thankfully, there are a number of No products found. on the market now that are not only aquarium safe but are also reef safe too.

These glues are exactly what you need for glueing rocks to each other or to other surfaces in your aquarium due to not having any effect on the water parameters of your tank.

Due to seeing such a large number of people reaching out and asking about using aquarium glue for rocks, we wanted to publish our own article sharing our thoughts.

We have collected all of the common questions that we see from the community about using aquarium safe glue in your tanks and added a table of contents below to make our article as quick and easy as possible to navigate.

The Best Aquarium Glue For Rocks!

The best aquarium safe and reef safe glue on the market for glueing your aquarium rocks has to be No products found..

Although there are some competing products on the market, nothing comes close to the performance and low price of Seachem Reef Glue making it the obvious options.

On top of the low price and excellent performance, No products found. also has an excellent reputation amongst the community for being beginner friendly and very easy to use.

This makes it the ideal option for anyone brand new to aquascaping who is working on their first build and wants a quick and easy method of glueing their aquarium rocks together.

Please note, you should have your rocks out of the water when trying to glue them with any aquarium safe glue.

This is a very common mistake that we see come beginners make so either has your rocks out of your tank or drain your tank allowing you to glue dry rock together and then add water once the glue has dried.

Can I Glue Aquarium Rocks Together?

You can glue aquarium rocks together with ease with a number of aquarium safe glue products on the market.

Some glue products that are aquarium safe do have a low glueing strength and may not work as well as others though but something like Seachem Reef Safe Glue is always a good option for glueing your aquarium rocks together.

Depending on exactly what you need and what you are glueing your aquarium rocks to, you may be better off using aquarium silicone sealant but this is usually for intermediate and advanced aquascaping.

The majority of our readers are just trying their very first aquascapes so something like No products found. will be the better option for a beginners needs while also being cheaper and easier to use too.

Once you have glued your rocks in place, we would usually recommend that you leave them at least a day before adding water to them.

Although some aquarium glue products do say you are able to add them much sooner than this, we always recommend you pull on the rocks slightly to make sure that the glue has worked and that your water flow in the tank will not be able to separate them.

This is usually not an issue with the better glue products but the cheaper ones really are not suitable for aquascaping with rocks and are just intended to glue live plants in place so may present a hazard.

What Can I Use To Stick Rocks Together In An Aquarium?

There are a number of suitable aquarium safe glues that are also reef safe on the market these days.

More and more silicon based products are also being released each year that will work well on rocks in some situations but these tend to be for advanced aquascapers where as the glue is a general use product for sticking rocks together.

Please note that the term “aquarium safe” and “reef safe” are not the same classification either. This is another common mistake that we have seen people making time and time again.

Aquarium safe glue is marked as safe for use with fish, snails, shrimp, amphibians, and invertebrates in an aquarium.

Reef safe glue takes this a step further and adds in sensitive corals and other live plants too and this is why a reef safe glue will workout to be slightly more expensive than an aquarium safe glue.

Due to many of our readers also having live plants in their tanks, especially if they are aquascaping, we always recommend you skip the standard aquarium safe glues and just go with a reef safe glue like No products found..

They tend to be around $5 more than an aquarium safe glue but they have been developed to have zero effect on your water parameters once dry making them a much safer option.

What Type Of Glue Is Safe For Aquariums?

There are a number of different types of modern glue formulas that are safe for aquariums on the market ranging from cyanoacrylate gel glues to silicone glues.

Not all cyanoacrylate gel glues and silicone glues are aquarium safe though due to the ingredients used in the formulas.

In fact, at the time of writing, the majority of cyanoacrylate gel glues and silicone glues are not aquarium safe due to the ingredients used in their formulas.

This is why we always recommend that our readers go with a specific aquarium safe formula from an established brand in the space rather than a generic cyanoacrylate gel glue.

As we touched on above, in our opinion, No products found. is currently the best option on the market but you can also use one of the aquarium silicone sealant products on the market too if you need a sealant.

This will come down to your own needs and what you are trying to do with your aquarium rocks though.

Can I Use Gorilla Glue In My Aquarium?

Many people do use gorilla glue in their aquariums but it is a controversial glue product to use. The official statement from Gorilla Glue is that it should be fine provided you leave it for its full cure time of seven days prior to submerging it in water.

There are a number of people who will outright refuse to use gorilla glue in their aquariums though. There are also some people who will only use Gorilla School Glue in their tanks due to it being non-toxic.

We would always recommend that you stick to something that is marked as aquarium or reef safe though to ensure that your water parameters are safe. Plenty of people do use Gorilla Glue in their tanks without having problems though so it will come down to your own risk tolerance.


That brings our article going over using aquarium glue for rocks to an end. There are more options available these days than there were even five years ago and with more and more people getting involved in aquarium keeping, there is more demand for better products with new products being released all the time. This allows you to quickly, easily, cheaply, and safely glue your aquarium rocks together without having to worry about possible contamination.