I found that the suction was low because there was no water in the hose to create a suction. If you have the water on full blast, close the valve attached to the end of the hose and the gravel vacuum and make sure the valve on the drain refill is closed so water is going in the garden hose but is not coming out anywhere. Once the hose is filled, you will know this because water will start to back up to the faucet, turn the drain refill kit to allow water into the sink. With the gravel vacuum in the tank, slowly turn it on and it will sputter till it fill, or if you have some tank water in there before you turn on the valve you wont get so much sputter. The suction will be very strong, I used this today and had to be careful not to suck up rocks. It's all about how much water is in the hose when you start the suction. I made mine for 25 bucks and i love it! hopefully this helps someone out. If not just say, "Hey, what the heck are you talking about!!!" and ill try to be more specific.

The DIY python works great for me. It cost me about $20 since I figured the misses wouldn't be too happy if I used a dirty garden hose for the job.... I used it for the first time today and the suction was perfect for vaccing and filling it was even easier. Just a little bit of advice though is to start with the vac end in the tank and turn the water on really low with the shut off valve in the on position. If you give it too much pressure it will either blow the fitting off the faucet or shoot water all over fish room.

I'd be interested in buying just the Faucet Pump without the other parts. Just don't know if there is anything available to connect it up to one of these:
http://www.hozelock.com/images/items/full/2274f.jpg

Another DIY from the Chiclid Forum:

http://www.cichlid-forum.com/articles/diy_python.php

Vic

Tried it and works great.

I got my Syphon that i had, Used a Reducer and connected it to length of hose(from the Special Offer at Aldi on 30 Metre Hose for 6.99). And, Viola really simple and easy to use.
I changed mine a little. I attached a hozelock Connector so that i just attach it to the Faucet using a male connector and turn the water on. As its such a big tank the cold water makes no difference to the temp in the tank, just cools it a little.

Just wondering before I build one.
The water will be added to the tank untreated and I will need to add conditioner (this is probably a simple question) but do I treat for the whole tank or just for what I have replaced. I told you it was simple but I am just unsure
Cheers Dave

For that, you might try a waterbed store. These types of things are essential when you have a waterbed.

Heres another little tip - If you really want to spend even more time drinking tea and sitting around make a stout U tube out of two solvent weld elbows and some over flow pipe. Attach it to the tank pipe with a Jubilee Clip and on the inside (tank side of it drill a small hole where you want the water level to stop - You can use the length of it to hoover the gravel then just hang it on the side of the tank and the hole will break the syphon when the water gets to the level you have set.

HTH

I've been looking into one of these, either a real Python, Lee's Gravel Vac or maybe making my own. But the one thing I was wondering was if you still needed the vac end to be at a greater height than where its going like in a traditional siphon. Or if beacuse of the suck of the faucet the faucet could be up higher than the rest of the tank. I ask this becasue my tank is in my room in my basement and I have a faucet right outside my window, but it is raised from the level of my tank.

Thanks, Pete