Be wary - my skin tank is closer to 30 litres. Overkill I think, but it is what it is.
In your situation the first time around, I undid the top hose and used a Pela type pump, which worked but it was when I found out the hose and spigots were mismatched and the "seal" was a bodge by the reputable boatbuilder's "plumber". Took me ages to stop the repeated weeping leaks and I only sorted it properly when I eventually replaced all my hoses as preventative maintenance at 10 years and did a proper job.
Antifreeze does have a corrosion inhibitor in it, but it's the degradation of this that means it needs changing, not the anti freeze properties. Trouble is, AF is also a bit nasty on paintwork, so I'd not be keen to drop it in the bilge. If you do get it in there, rinse and wet vac would be my course of action.