Pond to Pondless Waterfall Conversation

[MariaD311]

We are converting a 5x7 pond into a pondless waterfall. We have underlay, liner, hose, and a pump already. I'm purchasing a pump vault, aquablox, and the aquascape spillway... Please share any suggestions or guidance you may have! Are there any other supplies I will need? Once we have all the materials I'm going to pump out the pond, move all the rock to the side, remove the liner and underlay and then construct the basin from the pond hole. Is there any specific way to arrange the aquablox? And any benefit to 5 small blox vs. 3 large? Thank you!

 

[Lisak1]

I'd say to fit the aquablox however you can get the most in the space. Since we built ours I've learned that you can modify the blocks if you need to by cutting them down to size. We ended up filling our excess void space with softball sized boulders and scrap pieces of PVC pipe. There's no advantage to the smaller vs larger blocks or vice versa - all about what fits!

Take lots of pictures - this is a project that has been discussed a few times here on the forum, but I'm not sure if anyone has ever done one!

 

[MariaD311]

Thank you! Do you think I could do 2 large and 1 small?? That would be about an 81 gallon capacity and I calculated that I need 78.5... Would there be an issue with that? And how on earth do you arrange an odd number of boxes? Can we just dig out an odd shape or does it need to be rectangular/square?

 

[combatwombat]

@MariaD311: You can basically do whatever you want to get you to the # of gallons of storage you need. Doesn't really matter what size or configuration.

If your hole ends up being a little bigger than the shape of your aquablocks, just fill the voids around the edges w/ whatever stone will fit that is big enough to not fall through the gaps of the aquablocks. Or, you can pull your liner tight against the blocks and backfill the hole outside the liner w/ your leftover dirt.

As long as you get everything tight so that it doesn't shift around too much, you're good.

 

[MariaD311]

Thanks! I would like to get the little giant vault because it's $100+ less than the Aquascape vault but it's different dimensions than the aquablox (19.25 vs. the 16 blox) so there would be gaps when placing the blox... all the videos I have seen have had them flush against each other. Would these gaps be an issue or can I just fill with stone?

 

[combatwombat]

Would these gaps be an issue or can I just fill with stone?

Fill with stone. The only thing that matters is that water can get from inside the water matrix blocks into the pump vault so that the pump can suck it up.

 

[Lisak1]

My only experience with pump vaults is Aquascape, so I can't speak for anyone else, but I will tell you that the integrity of the vault is hugely important. The vault in my pond less is an earlier model from Aquascape and it's slowly collapsing in on itself from the weight of the gravel on the sides and top. They have changed the construction of their vaults in the ten years since we purchased this one, so I bet they learned the same thing. Shape and strength both matter. We will eventually have to dig ours out and replace it, or figure out a way to brace the sides or we won't be able to get the pump in and out much longer.

 

[Colleen_MI]

I just today got a quote from a pond company to build me a pondless. He quoted 5 small blox. I didn't think to ask why, but I'm guessing it's just easier to configure them. Or maybe they don't have to dig as deep? I'm new to this, though.

 

[combatwombat]

If the pond company builds based on Aquascape specs, then they would size their basin to be 2x the amount of water-in-transit in the stream.

5 small blocks is 85 gallons, so they must have estimated about 40 gallons of water-in-transit.