Marbles over undergravel filter?

[Gobrian44]

okay I took some shots last night they are not that good but hopefully I can explain whats going on here...

(excuse the dirty looking tubes, I havent cleaned inside of them in a LOONG time)

the undergravel filter trays for the 55gal has 4 exit tubes which can be placed at either corner of the 4 trays. these trays are all interconnected from bellow. the 4 exit tubes are all connected via a DIY 4-into-1 tube junction made of pvc. here it is...

and trying to see from behind the tank...

and one more from behind the tank...

in the last shot you can see the junction all ending up going into one tube that connects to the hose for the canister filter. the shot from the front of the tank shows the return from the canister filter that leads into the spray bar.

I looked through my videos that may show you more and this is the best I can find... it shows the transparent tubes, the black river stones and as you can tell te water and the rocks are clean given the dirty nature if it's inhabitants.

[YT]http://www.youtube.com/watch?v=Zu2kxC4hwis[/YT]

http://www.youtube.com/watch?v=Zu2kxC4hwis

You are the man. This is exactly what i was looking for. Is the substrate just those black rocks cuz i couldn't really get a good view of the bottom. And how does this work as far as your need to gravel vac?

 

[john73738]

Now that I have seen the truth, here is my idea to accomplish what you want to do.

Use gentle flow with the under grave jets to nudge the waste to the removal tubes.

Just my opinion

 

[Gobrian44]

so john your says two jets that push out from the center. Something like the green return piece in m1ste2tea's third picture. Is that what your trying to say? and thanks for the diagram. i wish i could make those.

 

[john73738]

This design moves the water under the UGF to herd the poop to the removal sites. In the above picture he is using a spray bar that works to aerate the water surface.

 

[Gobrian44]

right but i'm saying a spray bar under the UGF each pushing water towards the removal tubes...wouldnt that be more efficient than two jets becaus the spray bar would provide an even and constant flow to push the waste out.

 

[john73738]

OH gotcha, yes you would use a spray bar idea under the UGF plates, not just a couple jets. Sorry not clear about that

 

[Gobrian44]

well thank you so much i will have to start a thread when i start to do this.

 

[m1ste2tea]

Is the substrate just those black rocks cuz i couldn't really get a good view of the bottom. And how does this work as far as your need to gravel vac?

Yes, just the cheap river stones bought from the dollar store... I spent maybe $10 worth of them, just a thin layer, to conceal the undergravel tray...

And in response to johns idea, In theory it will not work as you predict it will. here is why; by putting the spray bar at the bottom of the undergravel tray and at the same time sucking up the water from the undergravel tray you are negating the suction force through the substrate, thus the waste will just collect on top of the substrate and not be sucked down through. This is a situation of "path of least resistance" that being right from the spray bar under the gravel and into the suction tubes. Yes, the water movement underneath whatever substrate you will have will create a pressure that is lower than the water above, but the difference is neglegeable.

John, I think this idea would only work if you have only a simple eggcrate, thus not allowing the waste to settle on any surface on the bottom... please disregard my objection if that was your idea originally.