Backyard Aquaponics
A place to discuss aquaponics

Slicone is not good, use Sikaflex and you will not have a problem.
Muzza

Muzz - which type of Sikaflex do you use - is it a potable one?

Yes, it is all potable, it is amazing stuff, leaves silicone for dead, could not build a boat without it. Zincalume tanks are jointed with it these days, very strong adhesive. It is polyurethane, moisture cured.
Plumbers use it, cars are glued together with it. Does not break down over time like silicone.
Muzza

There are different ones aren't there - can you tell which one you use Muzz.

we use sikaflex pro

where'd ya getit... that "B" place??

Hi Jamie, Pro is good and is avbl in most hardware stores. I use Sika 291 which is a marine grade fast cure, costs about 1.00 per cart more but for our use it is worth it. I plaster Sika over everything. "If I can't glue it, I can't do it" is my motto.
Muzza

I get sikaflex from the place my brother works at, cos I can get a discount. I get a 300gm tube for $11-13 depending on who processes the sale and the angle they have their tongue stuck out.

Hi all, (my 1st post!) lots of people with great ideas here. Im just starting my AP system and dont have a camera to post pics yet. I found that using selleys aquarium silicone worked really well when I made a glass aquarium and it sticks well to the white PVC pipe but its adhesion to blue 200L drums (does anyone use the term "mauser" here?) is weak. I can peel the silicone off the blue plastic with little effort (unlike with silicone on glass)
I didnt clean with mineral turps as suggested but they were new phosphoric acid drums washed with tap water so I expected all would be well.

The holes I drilled did thread when screwing in PVC plumbing fittings but when silicone sealed are still too flexible/ soft to let kids anywhere near, which is a problem. Im planning to replace the weaker joints with sikaflex as per this thread and will post results but before I shovel in my gravel should I replace all my silicone seals including those not subject to movement or risk it? Does sikaflex pro / 291 set brittle or flexible? Thanks:)

Hi Brett and welcome..... if you're going to replace some of the silicon seals with sikaflex... then you mightas well do them all.

When youre ready to post your system designs and pictures (:wink:) then start your own thread in the members area....

Oh and will sikaflex stick to the silicone I cant clean off?

you should be able to clean all the silicon off by rubbing it!
sikaflex pro will stick to most surfaces but oily substrates might need to be abraided.

I think those blue drums are some sort of Polyethylene -- (or polythene in the UK, not sure what it's called in Oz) I have not found anything that reliably sticks to it.

sandpaper, thanks

no probs