Under Gravel Jets (UGJ)

[swampy1972]

Have any of you out there used these before?
They're designed to keep the surface of the substrate free of contaminates and look dead easy to make. I'd hook it to a canister rather than have an internal pwr head, but that's JMO.
I was thinking they could prove valuable in eliminating dead spots in the tank and a good way to distibute CO2 enriched water in amongst the planted areas at the ground level.
I'd appreciate your thoughts and experiences.

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

[ILLUSN]

Discus like to graze off the bottom, you dont want to be blowing food all over the tank, maybe turn them off during feeds. To be honest seems like more trouble then its worth you sould be using the gravel vac on every water change if you have substrate.

if its just a planted comunity tank it would be great eventually all the muck from the bottom would end up by your filter intake for easy cleaning, I've seen similar systems and they work great, I even used one on my old turtle tank to bring all the waste to the filter intake side of the tank. words of advice, if using powerheads put sponges on the intakes to stop fry from being sucked up and it makes cleaning easier.

if using a canister make sure the pvc you use is at least the same diameter as the hose, it will make your plumbing easier and you wont overheat the moter.

if you use your only canister in this way add a power head near the surface for surface movement and oxygenation of the water.

[swampy1972]

Thanks Illusn,
You've raised some good points (as always). The intention is for use on a large planted community tank with localised planting and an open sand feeding area.
I envisage the jets to be focused mainly to provide movement around the planted areas, possibly some minor movement across the feeding area. The current would be very low as per my current setup that takes about 30min to move debris across the length of a 4ft tank. Unfortunately, I'm all to aware that I'lll never escape the gravel vac, but it may reduce the debris in the substrate and the potential for anearobic pockets.
As for the placing back pressure on the pump; if I have multiple outlets don't I cumulatively end up with more than the normal outlet hose diameter and therefore less output current and less back pressure?
Surface movement/oxygenation will be taken care of by weir/sump arrangement.
What do you think... am I on the right track with this way of thinking? :?

[cory1]

Interesting you should raise this subject,as i am considering using a reverse flow under gravel filter on a couple of 4ft tanks..it works in a similar way to your article but you only use 1 riser with a reverse flow power head
Coupled with this i will use an Aqua Genie air driven filter to collect the debris from the bottom of the tank..maintenance is greatly reduced and you remove fish waste before it can cause ammonia problems
There is lots of info on the net re these filters..reverse flush once a week and you don't even have to put your hands in the water :thumb

[ILLUSN]

sounds good swampy, multiple outlets help but you'll loose preassue from one outlet to the next unless you've fitted taps (generally you'll ahve 80% flow out the closest vent to the filter and 20% out the other)

[swampy1972]

Interesting you should raise this subject,as i am considering using a reverse flow under gravel filter on a couple of 4ft tanks..it works in a similar way to your article but you only use 1 riser with a reverse flow power head
Coupled with this i will use an Aqua Genie air driven filter to collect the debris from the bottom of the tank..maintenance is greatly reduced and you remove fish waste before it can cause ammonia problems
There is lots of info on the net re these filters..reverse flush once a week and you don't even have to put your hands in the water :thumb

Cory 1.

Do you have any links to the info on this idea? I was thinking of using a similar setup for dosing subteranian (spelling?) fertiliser for the planted pockets of my tank, but if I could get more uses from it then it would save the extra work.

Cheers.