How to resilicone a tank.

**Northernguy** · 10-09-2009, 12:16 AM

Many have been asking how to seal a tank so I thought I would write a short article about it with pics!

I was given a 20 gal a few weeks ago but couldn't set it up because the silicone in the corners had a bit of mold and it was beginning to peel.
I first cleaned it out really well inside and out.It had a lot of crusty build up on the top rim and on the glass.I first washed it out with a bleach and water mix and rinsed it out a few times.I used vinager soaked paper towel over the white crusty build up for a few hours. With an algae scrubber I started to come off,I used a razor blade to remove the rest and rinsed it clean.
Now that the tank is clean and dry I started to remove the silicone.I find it much easier to work on a clean tank.
With a flat edge razor and a utility knife I cut out the silicone.Be careful not to scratch the glass.There is less chance of scratching the surface if you dampen the corners first with a damp cloth for a bit lubrication.Just use water.
Be careful not to cut into the seam between the panels,thats whole other silcone job! lol I like the knife as a corner tool.Clean out all silicone debris from tank.I used a vacuum and the some alcohol to wipe down the corners with.

**Northernguy** · 10-09-2009, 12:18 AM

Once the tank is clean and free of all debris,wipe it with alcohol and a lint free cloth.There cannot be anything on the glass when you silicone.To keep your lines straight when adding the silicone use painters tape or masking tape.It makes the job so much easier.You don't want the silicone in the vertical corners to be too thick,I make mine 3/8" out from the edge.The bottom is covered by trim and substrate but it doesn't have to be any thicker.

**Northernguy** · 10-09-2009, 12:20 AM

I used Ge Silicone I 100% Rubber silicone.There are others that work.I trust this one.You will also need to have a roll of paper towel handy.

Make sure you use an aquarium safe silicone. The GE I that is listed in this thread is no longer available.That is the old product and it has since changed formula and is no longer safe.
Make sure use enough silicone that you won't have to add anymore later but not too much! lol Remember that the whole inside of the tank must be siliconed all at once.You cannot go back to it after it dries.Silicone will not properly stick to dry silicone.
I cut the end of the tube and leave an 1/8" thich hole.You do not need any bigger.After you lay a bead of silicone use a tool and wipe from one corner to the other none stop!It helps to keep from getting air bubbles in the bead which makes for a better seam. I used my finger but its not recomended.Start at the bottom and do the sides last,its makes it much easier to not bump your finished work leaving a neater finish.It also lets you get the feel of it before attempting the the areas you will see all the time.lol
Once you are done smoothing all your corners let it dry for 24hrs.

**Northernguy** · 10-09-2009, 12:22 AM

Remove the tape when its dry.I use a knife to cut along the edges.It makes the tape removal much easier and there is no risk off lifting the fresh silicone job.
Wait another 24 hrs before filling the tank.I test my tanks outside! lol Just in case.
I hope this helps to make the job easier.
Enjoy your leak proofed tank!

If I forgot anything feel free to ask!