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Need HELP!!!! Undergravel Filter to keep or not to keep!

Ok, OK, I think I made a mistake. I started a saltwater tank in late september and all is well. 29 gallon, 2 blue/green chromis, some turbo snails, and some blue legged hermit crabs. HOB and Undergravel filter. Tests all good. I do water changes and clean the gravel but now I think I want to remove the UGF now. I read on the internet how they are good to have then I read they are bad to have...I am going CRAZY. So now I think I want to remove it because I don't want to have to tare down the tank in a few years and since the tank is so young I figured I'd do it now before it gets too established. SO, whats everyones opinion? Keep or pull out. And if the consensus is pull it out, whats the best way to do it? Can I keep just the plate in since its so young with probably no biological build under the plate or should i yank the whole thing out? And, is there an excellent, quiet HOB out there that can also handle biological filtration. Keep in mind my tank is in my living room - so quiet it must be.
 

redfishbluefish

Officer Emeritus
Officer Emeritus
Well Old Salty, when I was breeding freshwater fish, this was my filter of choice for the fry.  You wouldn’t loose any baby fish into a “sucking” filter.  From a spawn of tiger barbs, I’d have hundreds of fish.  None lost to the filter.

With salt, this is another story.  I’m assuming you have some open “gravel” as a substrate.  You never have the possibility to establish anaerobic bacteria (don’t require oxygen to survive), in this kind of substrate.  These guys are important in the overall biology of the tank.

My recommendation…get rid of the UGF and the HOB filter and get a refugium going, or at a minimum, a protein skimmer.  I’m not up on the nano stuff, but I’ve got to believe refugiums are HOB, as well as protein skimmers.

The UGF is a nitrogen factory (nitrates) and it has to go! 
 
holy cow I thought this was a joke post.

first off - WELCOME to NJRC! glad you found us.

I have READ about some people who still maintain UGFs in a reef environment - but I believe it was mostly softies - and also the guy was doing some kind of very slow reverse flow.

POint being - it's do-able - but not ideal.

Man I feel like deja vu - i started with a 29 gallon and a UGF...but that was like 2 decades ago. I even had those pro-clear powerheads x4 inserted in each of the lift tubes with bleached white stag coral and a ton of crushed coral.

Honestly - if this is a FOWLR - I don't see the problem with high nitrates. Some other guy on the board had 80ppm and apparently it's not a big deal in a fowlr.

Biological filtration is typically handled thru Live rock.

You might want to take a step back and spend the $10~$15 or so bucks on a book to read. It will help you to distinguish between the advice on the internet and advice from the LFS.
 

Phyl

Officer Emeritus
Officer Emeritus
Welcome to the club! I do know that some folks are still running UGF, but if you're just setting up a new tank I would go ahead and pull it out. No point learning the pit falls with that when you could just do it using more current technology.

Live rock and powerheads would be fine, though I prefer an overflow for the increased water volume and oxygenation. There are lots of ways to keep your overflow "quiet".
 
I think the question may be do you stay with the substrate you have.

You say gravel, is this a crushed coral coarse kind of substrate?

If yes and you want to stay with that, then keep the UGF going and be prepared to continue vacuuming the gravel and doing frequent water changes. The problem with coarse gravel is detritus gets trapped in there before a skimmer or other external filtration can remove it. Therefore it will become nitrates that need to be exported through water changes. Phil also mentions the reverse flow method of forcing water up through the substrate to keep the detritus in the water column, but that still requires frequent water changes.

Most reefers who use any substrate at all will advise that you get rid of any crushed coral or coarse gravel and use a fine grade of sand. But if you are really in love with a coarse substrate, I would use a UGF.

If you have a deep sandbed, you can just remove the powerheads and the tubes and you have a plenum. This will function as the anoxic zone where anaerobic bacteria can breakdown nitrates into nitrogen. A host of folks will now jump up and down and cite the drawbacks of deep sandbeds and plenums. You need at least 5" of sand for this to work.

If you just have a shallow bed of sand or gravel that you will now remove, then I would lose the undergravel filter as well.

Now lets hear from the bare bottom crowd!
 
Is it in a room with Shag Carpeting? Please say yes!

First of all, I cant beleive some store would even sell you an undergravel filter. Please say it was not a vendor on here or a LFS.

I would yank it even it its not in use it will collect small particles in the slots in the UGF and build up over time.
 
Just remember Barry, leeches have made a comeback with the medical profession. ;)

Don't dismiss something just because it is old, evaluate its pros and cons and see if it works for your situation.

I kept many saltwater critters alive in the 70's and 80's with crushed dolomite and undergravel filters and I've seen many tanks crash with state of the art skimmers, calcium reactors and digital reef controllers.

Of course I've only experienced all of that because I am gettng old. ;D
 

Paul B

NJRC Member
First of all, I cant beleive some store would even sell you an undergravel filter. Please say it was not a vendor on here or a LFS.

I would yank it even it its not in use it will collect small particles in the slots in the UGF and build up over time.

Dam, I knew I was running the wrong system for the last 39 years :-[
 
Paul B said:
First of all, I cant beleive some store would even sell you an undergravel filter. Please say it was not a vendor on here or a LFS.

I would yank it even it its not in use it will collect small particles in the slots in the UGF and build up over time.

Dam, I knew I was running the wrong system for the last 39 years :-[

Took you a while to find this one Paul! ;)
 

Paul B

NJRC Member
Took you a while to find this one Paul!

I am on about 6 of these forums and a good percentage of people don't have the slightest Idea how to run a UG filter. It's not easy to find all of these posts. Especially being I am the only one running one. :-[

Of course, it has been running longer than most of these guys have been alive but thats besides the point ;D
 

MadReefer

Vice President
Staff member
NJRC Member
Moderator
Paul,
I have read this thread and yours about UGF. Can you elaborate by when you state if done properly. I am sure others would be interested in your method as it seems economical.
Mark
 

Paul B

NJRC Member
Mark, if you run a UG filter like it says in the instructions in the box in saltwater, it will crash in about a year. Trust me.

But if you tweek it a bit, it will last forever, be almost maintenance free, reduce nitrates, and be the cheapest system you will find.
Another nice part is that you can dig holes, move things around, add gravel, remove gravel and never have to add sand sifting creatures (unless you like them)
It also will never crash, even in a prolonged power outage. Mine has gone about 5 days with no power a few times. (now I have a generator mostly for the refrigerator but the tank runs on it also)

To make the thing work I plumbed all three of my "Uplift" tubes together. My tank is 6' long so I have 3 tubes. I ran the tubes along the rear of the tank on the bottom by bending elbows, but you can buy them. The three tubes all come up on one corner of my tank and they enter a small plastic container which used to be a HOB filter container. Any plastic container will work. The container is just about at the water surface.
I have a powerhead which feeds filtered water to the container. There is a sponge filter on the inlet of the powerhead because you don't want to push detritus down the tubes. I run 150 gallons an hour into the container so each tube gets 50 gallons an hour. Slower would be even better but no faster. If you run it fast, it will crash in a year.
You need gravel, no sand. I use dolomite. You can use crushed coral or any other type of salt water safe gravel. My grains are about as large as rice. My gravel bed is about 1 1/2 to 2" deep.
 

Paul B

NJRC Member
Here is a picture to show you the size of my dolomite. I just looked for a picture of this set up and it is not on RC anymore so if you need a picture, I will have to take one. But any system where you can push about 50 gallons an hour of filtered water under the gravel will work.
Also for all the other people that will tell you that a system like that can't work, ask them how many decades their tank has been running ;D

Gobieggs014.jpg
 

Paul B

NJRC Member
I forgot the maintenance part, everything that works needs maintenance.
That sponge filter or whatever means you use to clean the water going under the gravel needs to be rinsed occasionally and I also stir up the gravel where I can reach a few times a year with a canister filter and suck out the detritus. I use a diatom filter but any filter will work. I do that a few times a year. The fish love it.
If for some reason I have to remove rocks for maintenance or just re aquascaping, I stir up under there and suck out any detritus.
After 25 years I removed the rocks and stirred up the entire substrait.
I was curious as to what was living under there. It was mostly tiny red tubeworms.
This slow runing system will also reduce nitrates because detritus will limit water flow in the interfaces of the gravel particles. It will not be as efficient as a DSB at first, but a DSB will not last long and can not be maintained.
My nitrates are 5 and I only change 20% of the water about five times a year, I use some NSW from NY and I have to overfeed because many of my animals are spawning.
Also my gravel and rock is about 40 years old.
 

MadReefer

Vice President
Staff member
NJRC Member
Moderator
Paul,
Thanks for responding. From what you posted mine didn't work for probably 3 reasons.
1) I used crushed coral which is larger that rice.
2) I had two Aquaclear power heads on each side of a 30" tank pumping 30gph each.
3) I didn't use the sponge as I wa stold itn wpuld restrict flow.

I always wondered if I had one PH reversed and the other normal if that would work.

Mark
 

Paul B

NJRC Member
Running water down one side and up the other will not work. You can't filter the water on the side where the water comes up the tube. The trick is to get the thing flowing as slow as possable. In your tank, you probably could have gotten by with 10 GPH in each tube.
 
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