Silicone refuses to dry/Croc Skink Build

Hey everyone.
I'm building a bioactive paladarium for a pair of Crocodile skinks, not fish I know but I'm following a lot of the same aquascapeing methods for aquariums.
Step 1 was sealing the enclosure, which is a PVC enclosure, not a tank. But it's been over a week and the silicone is still tacky.
I thought it was the same 100% silicone I usually buy, but I'm starting to wonder if it isn't.
Here are some pictures.
This is the main issue with the enclosure. Unfortunately the skinks will be arriving second week in November so I am really trying to get it done before then, with a full week for it to cure.

I need to instal an acrylic panel in the front so the substrate can be deeper next. Then I've got to put in the custom background, the barrier between the water area and the drainage area where the pump will be, and all of the tank furniture.
The pump will push the water through the tube and into the water feature, croc skinks love water so it's important to me that they have a nice big space to swim, a little under half the enclosure will be a simulated slow moving stream.

But my main concern is the silicone. It's been over a week and its still like it was on day 1. Not sure what to do other than scrape it out and start over.

Warmer and air movement might help… if you hav a fan forced space heater… put it 3-4 feet in front of it, that should help it cure…

BTW… silicone doesn’t stick very well to acrylic

Glass silicon won't work on pvc. You need pvc glue or a silicon for pvc (assuming there is one).

Colin_T said:

Glass silicon won't work on pvc. You need pvc glue or a silicon for pvc (assuming there is one).

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It's worked on all my other pvcs to seal. Maybe I could get a terrarium liner in to waterproof.
Is there another material I could use to glue it together?

Magnum Man said:

Warmer and air movement might help… if you hav a fan forced space heater… put it 3-4 feet in front of it, that should help it cure…

BTW… silicone doesn’t stick very well to acrylic

Click to expand...

The acrylic is just to build a taller substrate barrier. Is there another material I can use?

you could go to a glass shop, & have them cut you a piece of plate glass just the right size

Magnum Man said:

you could go to a glass shop, & have them cut you a piece of plate glass just the right size

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I think I'd be better off finding a sealant that bonds to pvc and acrylic.
Looking into this right now.
It was sent to me with an Animal Plastics PVC for waterproofing, as long as it is fish safe it'll probably work for the skinks.
I did decide that instead of trying to seal everything with silicone I'm just going to glue in a plastic liner so there's no risk of leaking, and so the skinks never come into contact with the first layer of silicone just in case there is something wrong with it. It is 100% silicone so I can't imagine what the issue is.
I've also had a fan blowing on it for 48 hours now and though parts of it are dryer, it's still tacky.

I have used that brand as a glue for accessories… it’s not a “normal” silicone sealant, more of a glue, and I had the same issues with it seaming to take forever to dry, but never had issues with the fish, even if still tacky when things went into the aquariums

Magnum Man said:

I have used that brand as a glue for accessories… it’s not a “normal” silicone sealant, more of a glue, and I had the same issues with it seaming to take forever to dry, but never had issues with the fish, even if still tacky when things went into the aquariums

Click to expand...

Thanks.
That glue came with a pvc enclosure I bought to seal it after construction.
I don't have enough and now I can't find more online.
I did find this. Would something like this work? Might be the easiest way to fill in the cracks, if it is safe.