Reverse Flow Under Gravel?

[Lenny718]

Anyone use or have used a reverse flow under gravel system for corals and inverts? If so how did it work for you? Thank you in advance for your help.

 

[bklynreef]

sounds nostalgic. prehistoric even.
guess im showing my age, but i remember when that was the only way to keep a reef tank. They called it "The Plenum System"
:splitspin

 

[Lenny718]

sounds nostalgic. prehistoric even.
guess im showing my age, but i remember when that was the only way to keep a reef tank. They called it "The Plenum System"
:splitspin

Your correct "the plenum system" . My uncle was talking about when he had a reef tank back in the day and they used that system, Just wondering if its still in use?

 

[Wes]

Your correct "the plenum system" . My uncle was talking about when he had a reef tank back in the day and they used that system, Just wondering if its still in use?

Paul B still uses one. Look for his thread on his 36 yr old reef tank.

 

[autoponicz]

its still used...i seen this type of system in some LFS's

 

[Lenny718]

Thanks for the input guy's.

 

[NYreefNoob]

my lfs still use's it, i think most technich's work better, but the old one's work as well

 

[Lenny718]

My Uncle who is helping me and my partner build our new LFS wants to use the system for our coral and invert tanks so I wanted to get some feedback on it. Thanks

 

[bklynreef]

I wouldnt use it but thats just me. Seems old school and from my understanding its a nitrate factory under there but people have been using them from the get go. I personally would stick to a few inches of live sand and a refugium instead. This way you can stir the sand every once in a while and in section at a time to keep the old tank syndrome away.

 

[ILikeFish]

I have the a 3 inches of sand on top of some plastic screening / spacers and use a refugium. It is not an under gravel filter ie no pump. From what I understand it is a good place for processing nitrite.

 

[Wes]

One would think the hobby has advanced since the days everyone used reversed UGF and far more people would continue use this method if it were superior to "today's" typical reef tank setup. But one can't argue with success...

More than one way to skin a cat i guess..

 

[jhale]

this is a real interesting topic considering your thinking of using it in a large store display. I would not use this method myself but if you do please track the results for us to learn from.

have you figured out how the tanks will be plumbed yet? I'd consider a large remote sand bed and an attached fuge for macro algae only. these are similar in concept but if something goes wrong you can remove them from the display and still retain filtering capacities when your done working on the display.

 

[Lenny718]

We started plumbing for the fish tanks today, basically there's 3 large containers in the basement filled with live rock and live rock rubble and the water is pumped upstairs using a large swimming pool pump and then it returns back down to the "vats" or containers. For the fish tanks its a fairly simple method of filtration and we hope to start stocking the tanks in a few weeks if the levels are good. As for the "under gravel" system for the corals and inverts we still have a few bugs to work out but I will defiantly keep my buddies here posted on our progress and also hope you can come and see the system in action, maybe on frag night

 

[Chiefmcfuz]

I go to the same LFS rick does and all I can say is it works for him very nicely.

 

[Lenny718]

I go to the same LFS rick does and all I can say is it works for him very nicely.

That's great to hear Chief.So far I herd mixed reactions to this method on MR but If its done right it can work very well from what other LFS owners have told to me.

 

[Paul B]

You can make it work if you run it correctly. My reef is almost 40 years old and still running. You need to run it very slow and use some type of filter on the intake. I plumbed all three tubes of my 6' 100 gallon reef together in a manifold and use one pump. Each tube gets 50 gph. I have zero nitrates.

 

[Lenny718]

Hi Paul, Thanks for your post. One thing I can stay OUTSTANDING! But I have 2 questions. 1) If you where doing it all over again would you make half the tank reverse flow under gravel and the other half of the tank a plenum? 2) Would you do anything different than what you did from the beginning? Paul thank you in advance for your answer. Lenny

 

[Paul B]

Lenny, No I think I would do it almost exactly like it is now except for two small changes. This UG filter evolved a few times over it's lifetime. The plates remained the same but the manifold where the three tubes are plumbed together was changed for the better. In the beginning I diden't get the same flow rate from the manifold down the tubes but now I have all the tubes coming out of the bottom of the manifold so they all gat the same flow.
The thing I would change is the way I filter the water before it goes under the gravel. I used to have a 5 gallon tank behind the main tank with a filter screen that could easily be removed for cleaning but the main filtering was the 5 gallon tank itself. The water would siphon into the small tank which was the same level as the main tank and there was a pump in there to pump water to a manifold. I would get a lot of sediment in there that I could clean out before it went under the gravel. I don't have that anymore and use a sponge filter on the intake. I don't like sponges as I feel the filtering capacity is minimal. If I had the time I would put a 5 gallon tank back in the system but I would make the tank out of plexiglass with a sloped bottom. I would put a drain at the deep end of the slope to drain detritus out instead of using a siphon. I had a pull out filter in there but now I would also make a chamber for carbon for the times I use that.
I also would make it easier to siphon out water from the tubes. Sometimes when I do a water change, I siphon out the water from the "down lift" tubes. My manifold design makes that hard to do.
Paul

 

[Lenny718]

Paul thank you, your answers where very helpful. I just wanted to know how you managed after all the years to keep your nitrates at zero, I think thats amazing.