Sorry. Late to the party.
Yea you can use line lock connectors. If you want a permanent solution. Then solder it and shrink tube it.
Or a cold weld crimp. I’m a fan of the cold weld crimp if done correctly.
Look on fb marketplace. I haven’t tried any of those guys. But their prices seem super cheap.
https://www.facebook.com/marketplace/item/599368652639711/?mibextid=wwXIfr
You guys know most of those additives are garbage. Way expired. Do everyone a favor and junk it before someone uses it and it craps out their aquarium.