I was hoping someone can shed some light on this. I have a 12 x 30 Intex above ground pool. The stock filter doesn't really do anything. I want to upgrade to the filter to the 2,500 GPH Intex filter. I saw a youtube video on exactly how to do it using the hose adapter b which converts the 1.25" intake and outage to adapt to the 1.5" filter hoses that come with the 1,500 gph or higher filters. My question is that they also have these plungers valves which cut off the water for replacing or the filter cartridges etc... My pool came with a plug that I can use by inserting into the intakes. Must I buy the plunger or can the hoses fit right onto the hose adapter B? I am asking because the filter cost 79.99 on Amazon and no longer comes with the plunger valves. The valves which are sold separately cost an additional 90 bucks. I would love to skip them If I could for now.