Just for laughs, I thought I would spend a while figuring out that ACTUAL real life capacity of the pumps on Alchemy (as opposed to the ratings on the manufacturers box). The result were quite surprising.
The process was to add a known quantity of water, in this case 5 gallons into the bilge and then time how long it took each pump individually to pump it out. The video shows the full process including the math!
Manufacturers will often have their pumps listed as 1000 GPH or more. The GPH is gallons per hour. You can see in my tests though that my two pumps only managed about 200 GPH in real world conditions.
Considering that a 1″ diameter hole will let in 2,400 GPH, even with four pumps I would not be able to get ahead of the incoming water!