sealing drilled tanks?

Hey all

I have 3 tanks one was a sump the other 2 worked in a caflo system, I figured its cheaper in the long run to turn the 7FT sump into a fish tank rather then a sump my issue is.....

The 8FT tank has 2 45MM holes in the base and 1 45MM hole on the side,

The 2nd 7FT tank has 3x40MM holes on the side just below the roof bracing.

My idea is to use the glass that was used to turn the 7FT into a sump to seal off the holes with some aquarium silicon, by applying 18x5 inch or so of glass to each hole and silicon the **** out of it then press it down tight maybe lay a break on top fill the hole with silicon and do the same too the other side of the tank.

The glass I plan to use is 6-8MM and I am not quite sure how well this will work on the 8FT tank where its acting as a base sealer, I am pretty sure on the 7FT tank being on the side the pressure would be as great as in the base of the 8FT? My other idea for the 8FT if the glass is not thick enough is to use my 10mm or 12mm cover glass I got off a mate who planned on keeping massive jumping fish never told me what they where but I take it something pretty big for 10mm coverglass!

So I guess what I am asking is A. will my method work? B. Is 6-8MM glass going to be strong enough long term wise? C. How long should I let the silicon cure?

Thanks in advance guys, I did try the search option but found nothing!!!

I cant find bulk heads that fit, I tried a 34MM *top off my head* for the 40MM hole didn't fit thread was blocking it 40MM bulk head for the 45MM hole also didn't fit, the store told me they don't know of any other sizes?

also if I install a bulk head I have to cut out the shape from the wood so it sits flat, My jigsaw is lost lol more costs!!!

So lets say I use bulk heads? what sizes would you recommended? I can try to find them but finding the 2 I already have was a mission and a half boy was I pissed!

The hole sizes are.. 45MM and 40MM, Pretty sure thats a 40MM bulk head for the 45MM and a 32-4mm for the 40MM hole? Not 100% sure as I have nooo idea about plumbing etc Id trust myself rewiring a house before I re did all the pipes! also should be asking a special type of bulk head? could this by It did not fit? and as I am sealing it shut I take it adding some silicon wont hurt?


also why I have some people here, I have a broken 6x2x2, when i filled it the front seal let go and about 3-4ft gap, now to repair this do I just add silicon into the gap maybe add some brace glass? or do I have to tighten the glass so it sits right against the base * remove the gap from the front part and the gap so its sealed more tight*?

Thanks everyone means a lot!

Thank Zari, is this a must even if the sides are fine? I dont think id be able to fix it if I remove the whole front panel how would I get it laying flat and allow the silicon to dry without some kind of special bench or lots of clamps? any idea about the bulk head sizes also? I have been doing some googleing and a 1inch bulk head should of fitted the 45MM hole so I am lost even more else the bulk head I used for a special one :S

Thanks Pharahoh! I think I will try the glass method first, I have 8MM glass laying around so nothing to lose over 100$ for bulkheads! Did you add glass to both sides of the hole? or just one side and silicon the other side?

I might try to remove the silicon from the open area first then seal it if that fails I might remove the front panel or just use it as a lizard or snake tank, I cant wrap my head around balancing a 6x glass onto the frame and keeping it tight lol.

Thanks again I will post some pictures when I get the glass cut!

Alrighty, I tried to cut the glass the the tool required but It would not bend so I got pissed off and well hit it with a hammer xD then I noticed I produce 5-6 Perfect parts not square shaped but covers the holes great so applied 1 tube of silicon to all the 3 holes and the glass placed the glass on the inside after cleaning with rubbing alcohol and letting it dry, then placed the glass down pushed hard until all the air bubbles where out once this was done I placed a brick on top to add pressure, tomorrow my plan is to turn the tank over and seal the other side of the hole with lots of silicon hope this works then I will try the 8FT tank if I managed this one!