Water Movement, Under Gravel Jets And Dead Spots?

[des22]

Hi All

I had i look at this article about making underwater gravel jets.
Under-Gravel jets

Is it that important to have something that can move the water around?
What about the fish can they handle alot of movement, i know you get some fish who need water movement and some that need still water. But generally speaking does it mater if there is alot of water movement, can it cause problems with the fish?

The guy who wrote the article claims that the need for vacuuming as been eliminated which sounds great.

 

[Aphotic Phoenix]

In freshwater systems it's not really as necessary to avoid "dead spots" as it is in marine systems. A really good idea for some set-ups (rocky set-ups are a pain because detris easily builds up in places that can't be reached by a siphon), but might wreak a bit of havoc on a planted tank.

 

[K-Holed]

Hmmm ... so basically it's a reverse flow UG filter ... or did I miss something?

 

[waterdrop]

Really a very interesting article des, thanks for posting the link!

~~waterdrop~~

 

[Corleone]

That's what it sounds like. I don't think I'd like something like that - I imagine it blowing fish poop up out of the gravel and making a godawful mess, but it's probably nowhere near like that.

Good gravel cleaning should be enough to avoid dead spots. In a planted tank where you can't do too much without chewing up roots, a lot of people swear by burrowing Malaysian trumpet snails.

 

[waterdrop]

Yes, I agree, def sounds like not the thing for planted tanks, but still is quite thought provoking and sounds interesting for larger tank, larger fish, non-planteds it might seem.

~~waterdrop~~

 

[des22]

Do you think that it may be worth trying out? I understand that maybe in a planted tank it will not work to well. But maybe in a freshwater community tank.

I was thinking of using the idea as the return from a wet/dry filter. I guess you would also have to be careful how strong the water "jets" out, dont want fish getting pushed around.

 

[K-Holed]

Reverse flow UGs have been used for years with sucess, as have normal UGs. As people have mentioned it does cause roots distubance to plants however. With today's efficent filteration systems, with their high surface area media, they tend not to be the prefered option now.

 

[des22]

In the article it does not seem that he made a reverse under gravel filter. It is actually pvc tubes under the gravel and the jets stick out the gravel to move the water in all directions.

Sketch diagram image click here

Image of jets click here

The jets sticking out might look ugly, but like he says you can stick gravel to the jets to disguise them. Thinking about he has plants in his aquarium seen in the images in the article. I would think then the jets are moving the water above the gravel cause the water is not being pushed out from underneath the gravel. So they might not disturb the roots.

From article;

"What's so neat about UGJ is that they are highly customizable. People have used them with gravel and sand. Some creative adaptations that I have seen are first gluing the PVC to the bottom of the aquarium with silicone to prevent them from being dislodged by diggers. Others, in an attempt to disguise the white PVC, have covered the PVC with epoxy and then glued their substrate to the top of the pipes."

by Marc Elieson

 

[dthoffsett]

For freshwater systems you mostly see UGJ's in mbuna tanks (rock-dwelling cichlids of Lake Malawi, Africa). This is because most mbuna tanks have a large amount of rocks for territories. It's not pratical to remove the rocks during water changes, so the UGJ's keep waste from building up in the caves/crevices.

I would suggest them for fish who enjoy a higher current, or are 5 inches or larger to give them a fighting chance.