I recently fixed an oil leak in my subaru, after about a month of it sitting, and came to find that in the down time a huge leak has formed from directly under the water pump. It is coming out right under the water pipe slanting down from the drivers side, I am assuming it is just a seal that needs to be fixed but was wondering if the gasket in a tube will work.

Can you tell if it's coming from the water pipe (sealed by an o-ring), from the water pump-to-block seal (sealed by a gasket), or from the shaft seal (sealed by a rubber seal)? If it's just leaking from where the water pipe goes into the pump, replace the o-ring, put some RTV in there, and you're good to go. If it's hard to tell or you think it might be leaking elsewhere too, just get a new waterpump and gasket for like $40 and seal it up right. My personal favorite sealant for water pump gaskets is the spray-on copper stuff.