A couple of months ago, I posted about using short PEX pipe to vacuum your substrate in tight spaces. I mentioned that using the short PEX pipe allows you to especially vacuum sand because it's draw strength (suction) is less and it has a much smaller intake than the gravel tube of a Python or similar gravel cleaner.
What I didn't really discuss in that previous post is exactly how I use the PEX in the whole vacuum process. Yes, I use it as a gravity siphon, in which the water goes into a bucket. However, the bucket never fills up. Why? I insert the gravel tube of the Python into the bucket with the other end connected to the faucet in the usual way. Though I could step a Python hose at the faucet down to the 1/2" OD of the PEX hose, I don't because I don't want to create super suction. With my sand substrate, too much suction makes vacuuming too large of a challenge.
In the photo below, you can see the PEX hose in the back of the bucket with the Python gravel tube inside the bucket in front. Because the PEX hose is so small in diameter and lightweight, it's hard to keep it inside the bucket. Thus, notice the binder clip on the rim of the bucket being used to anchor it.
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