WaterWar.net

I've never owned a backpack blaster before, but I've always wanted to have a massive supply of water handy. Unfortunately, the CPS 3000/3200 is prohibitively expensive, the SS 300 has too few nozzle options for my purposes, and the SC packs depend on QFDs. So when I saw a rare Hydra Pak on eBay for only $47, it seemed too good to pass up.

Some observations:
• Filling it takes some time. I feel like this is the most water I've ever put into a single container at a single go. You could be in trouble if you were in a war, and this was your only blaster and you had to fill it up.
• The pump seems to get good volume, but looks slightly flimsy, and is genuinely hard to use. I managed it, but I'm not sure a kid would.
• The bladder doesn't contain all of the water, so there is theoretically a time when you might have to repump the blaster before refilling it. This likely requires taking the pack off. This isn't an issue for any of the Super Soakers - the high-ends because the blaster has the pump, the SC packs because the storage is all bladder and they're pressurized when they're loaded. The Hydra Pak, by trying to throw a pump onto an SC-like design, gets the worst of both worlds. Water Warriors' team might have thought this through better.
• The blaster itself follows the Super Charger model and is essentially a fancy hose nozzle.
• I read the Hydra Pak has poor range. This is an exaggeration for the smaller two nozzle sizes, which seemed comparable at least to my SC 600, but it is true for the largest one (the water comes out of the blaster visibly slowly) and for the fan spray. I'm not an expert in any of the sciences, but I suspect the issue here is fundamentally because of the hose. If the blaster was carrying the bladder, I guess we'd see better big-stream performance, as the CPS blaster apparently has.
• However, this does have redeeming value. While the big stream is a poor combat setting, it seems like it is a great size and flow for getting water into other blasters' reservoirs, good for using the pak as a resupply tank.
• I've never worn a backpack, so I don't have much experience, but I'm genuinely uncertain about how to put this on, or if it's even possible for a larger person. I was able to eventually manipulate my way into it, but then experienced 'tyrannosaurus arms' and a large amount of pressure, and required help to get it off. I'm pretty sure I did it wrong! This is a bit of a 'gotcha' if it's not just user error, and there's no solution to it; it would be a blaster that really is best to have an adult pump, but can only be worn by a child.

Quick Takeaway:
Strengths: Good fire time, great water supply
Weaknesses: Poor ergonomics, low range for highest-volume nozzle.
Recommend: Yes, as a sidearm and refill tank, or as a primary in lower-end wars - if the price is right.

Thanks for posting, interesting review. I seem to have missed this blaster when it came out and I had to check iSoaker for photos and other information.

I think you're probably right about the hose limiting the performance. In a backpack homemade blaster with a pressurized chamber in the backpack, I was able to get significantly better performance with a hose around 3/4 to 1 inch in diameter as I recall. That'll have far less pressure drop from the hose. But thinking about it now, there's a lot of water in a hose that large, so this increases the weight.

I do like the idea of backpack blasters, but putting the pressure chamber in the backpack presents performance and ergonomic issues, so I guess it's rarely ever done.