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Aquarium silicon sealant is ideal for many fish tank applications where an aquatic life-safe, long-term, permanently flexible bond or seal is required.
It’s both useable on the fish tank unit and equipment such as filters, pumps, decorations, and glass panels.
Depending on how big your tank is and how thick the silicone applied is, most sealants are touch dry within a few hours and sets in a day (24 hours) or two (48 hours). However, full strength is usually not attained until after a week or so.
If your fish tank is quite large, leave the silicon for 2 weeks to attain full strength. Smaller aquariums should be strong enough in about a week.
But please keep in mind that silicone sealant curing times vary from one manufacturer to the other. From experience, most product makers recommend giving the silicon up to 48 hours before adding a substrate and water in the tank after application.
Also be sure to use clear-aquarium-safe-sealants only. Even so, the silicone applied may still leach out into the tank and cause brown algae build-up for a few weeks until all the silica is gone.
See more insight below.
How to Make Aquarium Silicone Dry Faster
The time it will take for your aquarium silicone to dry will be much longer in colder or damp environments. Consequently, the easiest way to hasten the curing process is to raise the ambient temperature.
Usually, the stated 24 hours curing period is premised on a temperature of around 77 degrees Fahrenheit and a 50 percent humidity. As such, any better setting should help it cure faster.
Even so, please note that direct heat application is not recommended. If you must, go with something like a heat lamp placed a few feets from the sealant you need to dry.
You can also use a blow dryer to direct warm air onto the silicone sealant to help it dry faster. Remember to keep the dryer at a moderate temperature setting and stay at least a foot away from the adhesive.
Where a fast, low-temperature cure is needed, an excellent choice would be a versatile, silica-filled, addition cure general adhesive. It can be fully cured in one minute and, when adhering to temperature-sensitive substrates, provides a fast-cure choice.
Humid environments with a warmer temperature setting will cure silicone faster, but direct heat to hasten the process is not recommended.
What Happens If Aquarium Silicone Sealant Gets Wet Before It Cures
Aquarium silicon sealant should be kept from getting wet before it cures, meaning you can only add water to your fish tank once the sealed part is fully-dry.
As mentioned above, the average time it takes to cure sufficiently and before you can expose it to water is anywhere from 24 to 48 hours. Getting the sealant wet prior will result in a weak finish, plus extend the curing time.
Overall, water added on uncured sealant forms a mass of moisture that take a long time to evaporate, compromising the integrity of the caulk, and making it difficult to achieve proper adhesion.
Too much moisture can also lead to the growth of mold and mildew.
One last thing to note is that aquarium sealant leaches a small amount of acetic acid and silicates, which will affect your water quality if it gets wet before setting correctly.
How Long to Wait After Resealing Your Aquarium Before Adding Water
We’ve already seen it takes up to 48 hours for aquarium silicon sealant to dry enough for you to add water in your fish tank. But if you need it to attain full strength, you might have to wait for 4 to 7 days.
Plus, it also depends on how much resealing you’ve done on your fish tank. If it’s just a small fish tank that would barely cause a lot of trouble to dry, then waiting a whole seven days is a little overkill.
Another factor that would dictate how long to wait is your silicon’s manufacturers. Different products might have varying specifications on how much to use and how long to wait till it cures.
That said, a common way aquarist check whether their tank is ready to take fish after resealing is the smell of vinegar. Because curing silicon releases acetic acid while it dries, there usually is a subtle acidic smell, which will go away when it’s dry.
How Much Silicon Do Your Need to Reseal an Aquarium
The amount of silicon you need to reseal your fish tank quite often depends on how large your tank is and the thickness applied. But overall, two tubes should be enough for any tank less than 125 gallons.
This implies you need two 10.3 ounces tubes to seal a 125 gallons fish tank, and one container for a 55 gallon. For a smaller or bigger tank, stagger this estimate accordingly: either up or down😎.
That all. See you on the next one✌.
Happy fish🐠🦐 keeping.