Gathering information on UGF's

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Johny

Aquarium Advice Freak
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Utah
I would like to ask for your help in gathering information about Undergravel Filters.

Before you respond to this post with "Those are worthless and outdated, get a powerfilter/HOB/Canister filter" please read this entire post.

I have seen ALOT of posts and threads that bash on UGF's and state that they are worthless and outdated. I happen to have one (came with the used/established tank we first bought). As I sought to better understand how our new tank equipment functioned I became aware that there was a great disparity in how people talked about UGF's. Most people that dislike (or more realistically, hate) UGF's did not link their dissatisfaction to any personal experience with them. On the other hand the few that like them usually have years of experience with them and can very articulately explain why they like them.

What I would like from you:
Personal experience with UGF's (good or bad)

It would be very helpful if you could provide as much information as possible...
What type/model did you have (risers with airlines/air pump, power heads, etc.)?
What size tank?
What fish you kept?
Type of substrate? Depth of substrate?
Maintenance you did (method and how frequent)?
How long you used the UGF?
Why you got one in the first place?
Any training or research you did to know how to use them?
Method of testing water parameters?
Frequency of water changes?
Did you have live plants?
Did you even attempt them (live plants)?
What plants? What fertilizers?
Anything else you can think of that would be helpful or pertinent?

If you know someone who has experience with UGF's, I would appreciate it if you could direct them this way.

Please please....PLEASE don't turn this into a bash. I am not advocating UGF's nor am I trying to discredit them. I simply want to hear personal experiences with them so I can better understand them. If you don't have any personal experience with them, I invite you to follow this thread and learn from those who do have experience with them.

I know UGF's tend to invoke strong emotions, please know this is not intended to be a debate. Please remember the forum rules:
"We take the "be nice" rule VERY seriously! We do not tolerate ANY rudeness."
 
I'll play along. :D Granted, I have a partial UGF setup, but this is my experience...

What type/model did you have (risers with airlines/air pump, power heads, etc.)? (2) 12"x12" Grates, (1 on each side of my tank, leaving the center 24"x12" area open for live plants), (2) Marineland Penguin 550 Power Heads
What size tank? 55g
What fish you kept? Community Fish
Type of substrate? Depth of substrate? Standard Gravel, 2"+/- Deep
Maintenance you did (method and how frequent)? Weekly Maintenance w/ Gravel Vac and Reverse Airflow, (air hoses placed beneath UGF grates to push debris up through power heads).
How long you used the UGF? 4 Months
Why you got one in the first place? To help decrease time to perform maintenance.
Any training or research you did to know how to use them? Online research only.
Method of testing water parameters? API Freshwater Master Test Kit
Frequency of water changes? Weekly
Did you have live plants? Yes
Did you even attempt them (live plants)?
What plants? What fertilizers? Low-Medium Light Plants. Seachem Flourish (Liquid & Tabs), Seachem Excel
Anything else you can think of that would be helpful or pertinent?
I used my partial UGF setup in addition to (2) HOB filters. After 4 months of use, I have removed one of the grates due to debree clogs. I plan on removing the other one within the next few weeks. In the interim, the power head is a hot-spot for my Bamboo Shrimp. lol

My original plan was to use the UGF's to help eliminate the need to do extensive gravel vacs on the sides of my tank. The center, (24" wide x 12" deep), is where I have all of my deep rooting plants, so I wouldn't need to gravel vac in that area.

Low and behold, the UGF's failed and didn't help decrease the amount of time to perform maintenance... it increased it. Even with air hoses beneath the grates, they only pushed some of the debris out. In order to remove the remainder of debris, I had to place a gravel vac flush against the grates and suck up the debris through the slits on the grates.


In short, I think if the grates were taller it would allow for more debris to flow freely beneath them and get sucked out by the power heads.

More info about the partial UGF setup is in the thread in my signature, ("Low-Tech/Low Maintenance..."). I haven't updated the thread in awhile, so there's no mention about the (1) UGF being removed.

Hope my input helps. :D
 
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I just bought a 55g from a guy who kept cichlids. It had an undergravel filter and an HOB I considered doing both and then threw out the idea bc of everyone's reaction to the idea of the UGF. I decided to go with PFS which cannot be used with the UGF so that helped determine my decision. Also it was FILTHY under the filter and gravel. Seems like I couldn't get the gravel clean...( b4 I went with PFS) Another reason I decided not to go with them. I didn't want to eventually have to uproot everything to get it clean under there,... Lol! However I have heard mixed reactions as well.
 
McLumpy - I am confused about something with your set up. You mention using powerheads, but then you state that you have an airline under the plates? Where you running both the powerhead and airline to the same plate at the same time? Maybe I am just not familiar enough with powerheads, but I thought they didn't use airlines. Also were you running yours in the traditional flow direction (pulling water down through the gravel) or a reverse flow (pushing water up through the gravel) ?

Anyways, thanks for the response. Exactly what I was looking for.

Flossie - I can understand being turned away from them by what you found underneath. We found a similar amount of crud under our plates from the previous owner. We chalked it up to them not knowing how to maintain the tank rather than a flaw in the filter. I spent about an hour or so with the previous owner picking his brain about how he maintained his tank before I took it off his hands. It only took me about a week to realize how little he and his wife knew about keeping fish. They were the classic go to walmart/petsmart for advice (never looked at a forum) fish keepers.

The mixed reactions is exactly why I want to gather more info and experience about them. Thank you for your input.
 
My wife recommended that I add a bit about where I am going with this and/or what my motive is.

I am a very analytical person. I like to research and understand things. I want to know why they work/don't work. I would rather have enough good information to make informed decisions and have informed opinions.

I have read through several debates (and participated in one) that have spark my interest. Just hoping anyone with any personal experience can help me in my quest to know more.

Here is a link to the last thread that helped spark this thread:
http://www.aquariumadvice.com/forums/f20/advice-on-ugfs-needed-please-162021.html
 
I have used them multiple times, personally and at stores I worked at. I have never had one work out long term.

What type/model did you have (risers with airlines/air pump, power heads, etc.)? Always used powerheads, not sure about the various types.
What size tank? 10-90 gallons.
What fish you kept? Everything (one shop used them in all tanks)
Type of substrate? Depth of substrate? Gravel, 1-2"
Maintenance you did (method and how frequent)? Weekly gravel vac
How long you used the UGF? years
Why you got one in the first place? had used ones from used tanks or store already had them running
Any training or research you did to know how to use them? No training needed, vacuum them EVERY week and hope for the best
Method of testing water parameters? liquid test kits
Frequency of water changes? weekly
Did you have live plants? not that I recall
Did you even attempt them (live plants)? not that I recall
What plants? What fertilizers? N/A
Anything else you can think of that would be helpful or pertinent? I have used both UGF and RUGF and neither work out long term. In both cases you are using a filter media (the gravel) that you CANNOT take out of the tank, drag to the bath tub, and clean WITHOUT making the tank look like the city has been pumping sewage through your tank. Most people suggest running additional filtration with UGF, as in don't run just the UGF, run UGF and a HOB. This means that you can buy either a HOB, UGF, and powerhead(s) OR a larger HOB. Which is cheaper? With a HOB or canister if you neglect them you can simply turn them off, take them to the tub, and clean them without releasing a load of sewage into your tank. That is not the case with UGFs. Having a filter that absolutely has to be cleaned every single week ever and even then may turn in to an in-tank septic tank is not the best way to go. Not to mention that sometimes life happens and there are higher priorities than a gravel vac.

When I broke down the RUGF on the 90 gallon at one shop I was working at it turned the tank into a brown mess. Visibility was literally about two inches. And that was after vacuuming as thoroughly as possible two days in a row before pulling the substrate and UGF.

With all the options for filtration today I see absolutely no need to use UGFs. There are other more effective, easier to maintain, and much less likely to turn into a problem.

In addition, sand is a much better substrate anyways. It is more natural, much cleaner than gravel (with or without UGF), and almost maintenance free (or is maintenance free). And since UGFs don't work with sand, it is pointless to discuss them.

IME the people who like UGFs are the people who have been using them since the 80's when they were the best option. They figured out how to use them without major issues and have stuck with them.
 
I have used them over the years and understand why people don't care for them, but there is a lot of mistruth deseminated by many. I used a variety of different styles of plates, some full bottom coverage and others only partial, starting in the 60s, mainly because they were effective and economical. All were air powered, conventional flow, and had about 1 1/2" to 2" of 1/8" gravel over them. Plants were hit and miss when grown with UGF. Maintenance was sporadic although water changes were done usually weekly or bi-weekly, and usually with a gravel cleaner although not always. The last one I had in use went 12 years without a tear down.
The complaint about debris build up under the plates is easily rectified by siphoning through the lift tube. This would result in the vast majority of what was under there being removed. This I saw when I checked the tank bottom from below while siphoning. The term "nitrate factory" is often used to describe a UGF; this applies to all filters as that is their purpose. UGFs don't create any more or less nitrate than any other form of filtration. How much nitrate do you think is created by a cannister that goes months between cleanings? The debris is in the can rather than under the plates, but it is still there, and must be considered still in the tank.
If you have fish that dig, which is most cichlids, they can disrupt the filtration and this is a drawback. However, for many years many people kept cichlids in tanks with UGFs.
With reverse flow UGFs, there is normally a sponge prefilter on the powerhead so there should be no buildup beneath the plates or in the gravel.
As far as whether sand is a better substrate is a matter of opinion. For many years gravel was advocated as a superior substrate to sand, for a lot of reasons. Sand is not more natural, cleaner, or less maintenance. I have one tank with sand right now, and it is a pain to clean without removing a large amount of sand. I am not sure I like it, but will continue to use it for the time being.
Most of my tanks actually have no substrate and are filtered with air driven sponge filters, although I have the one with black blasting sand, and 5 with gravel, 3 of which are planted. The planted tanks aren't gravel vacuumed so there is less maintenance than an unplanted tank with substrate.
So, while there are many great ways to filter a tank, the UGF is still an economical option for a cheap set up, although the least maintenance is a bare bottom tank.
As a side note, the local Big Al's has a least 100 tanks of all sizes that are filtered using UGF powered by air, and while the tanks are regularly cleaned, they also carry huge fish loads.
 
Siphoning through the lift tube only removes the debris immediately adjacent to the lift tube, which due to flow will not be where most debris settles.

Yes, any filter that is neglected will collect massive amounts of debris and turn into a nitrate factory (although this is not the purpose of any of them). This is why monthly filter maintenance is essential for any filter. However, if I neglect my FX5 I can drag it outside and clean it, removing every bit of debris without polluting the tank. This is NOT the case with UGFs. If you neglect them at all you have debris that you simply can't get back out without a break down.

I think we all know that no filter media is 100% effective. This means that even with a great prefilter on a powerhead there will still be debris getting down below the plates. Not to mention that even with a lot of flow going down the RUGF you will not have enough flow to push debris out of the gravel throughout the entire gravel bed. So you will still get debris under the UGF plates and in the gravel, just like a regular UGF.

Sand is much more natural. Effectively none of the habitats that any of our fish come from have gravel as a substrate, it is sand or finer. The type of sand can make a massive difference in how it runs. I prefer one particular brand because it is so uniform and the perfect grain size. Using other types may lead to many of the problems people cite with sand in general, even though it has more to do with the type of sand. If you have enough flow the debris will keep moving until the filters grab it. If you don't you should have a few piles of debris that are easily removed by holding a siphon or gravel vac over the debris, removing very little to no sand.

I worked at a store that used UGFs. Yes, it can work out well enough, but they also have a fill time staff dedicated to sales and maintenance. If you want a fill time job cleaning tanks or want to hire someone to do that, get a bunch of tanks and use UGFs.

I have worked in many stores and had many tanks over the years, all with different methods. My current methods allow for ease of maintenance while having the most effective filtration and maintenance when it is done. This includes sand, strong real filters (canisters or large HOBs, like the AC110 I just put on a client's 37 gallon), and large weekly water changes. This means healthy, happy fish with minimal but very effective maintenance on my part. This means easier for me and more time enjoying the tank rather than vacuuming it.

I would NEVER suggest using UGFs for any of my customers or clients. If I did it would be because they require weekly maintenance (meaning I would have to go and maintain the tank, good for business).
 
This is already turning into quite the resource. Thank you all for your responses! Imagine what it will be like when more people add to it (I know there are more than five of us who have experience with them).

I guess what we are doing is creating an equipment profile of sorts. With enough people contributing their experience, we will be able to direct anyone who is thinking of getting one, or has one and doesn't know how to use it, to this thread. They can then become informed, and make a decision.

You know it wouldn't be a bad idea to create a similar thread for all major equipment...
 
McLumpy - I am confused about something with your set up. You mention using powerheads, but then you state that you have an airline under the plates? Where you running both the powerhead and airline to the same plate at the same time? Maybe I am just not familiar enough with powerheads, but I thought they didn't use airlines. Also were you running yours in the traditional flow direction (pulling water down through the gravel) or a reverse flow (pushing water up through the gravel) ?

Anyways, thanks for the response. Exactly what I was looking for.

Sorry for the delay.

The power heads were operating in traditional flow direction. An airline was placed under each plate but was only turned on when I wanted to clear the debris out from under the plates. When I turned on the airlines, some of the debris loosened and got sucked up through the powerheads. My HOB's took care of the rest. :D

I was impressed w/ the setup at first as it worked well to clear the majority of the gunk. But, even w/ a weekly pwc, I just couldn't keep up w/ it. The height of the plates contributed to the debris getting stuck and increased the amount of time to perform maintenance on my tank.

In short, the UGF's would have worked better in my tank if they were a little taller and if I didn't have a lot of messy fishies. lol So, until they redesign the plates and my bioload decreases, I'll just stick w/ my HOB's. (y)
 
@ McLumpy

No worries on the delay. The info still got here. That clears up a lot of confusion. I had a hard time imagining how you were using both powerheads and airlines on the same UGF's. Makes sense now. Thanks for your contribution to this.

Maybe nobody will ever use it, but I tried to gather it (info) so anyone who is curious about UGF's can learn about them from our experiences.
 
I can't give you specifics because it was about 25 years ago. I had a 55 gallon freshwater with UGF. I had neons and a few others. I could not get it clean underneath the grate. I remember having those 2 cyliners with a flow nozzle at the top and were at each corner with a couple of pumps. There was some air lines to decorations (treasure chest bubbler). But I remember trying to clean and having to move the gravel (I used blue and purple) to clean and when I'd move the gravel, the grates would also come apart and I would have to move the gravel again to put it back together. I moved cross country and sold the tank setup. I'm just now starting again but in Saltwater. Hope this helps.
 
I LOVE that you are doing a study on this subject. I, too, have wondered about why some people love UGFs, and others dislike them so thoroughly. I am glad to throw my opinions in to the mix.

What type/model did you have (risers with airlines/air pump, power heads, etc.)? My first UGF was in a large glass cookie jar, with one fancy goldfish. (Yes, not a good setup, but I was very young and not too wise.) I knew the fish needed a filter, and the only filter that would fit on that cookie jar was a UGF (driven by air bubbles, yeesh.) Later, that fish moved to a 10 gallon tank, and I went with a UGF again because I already had the air pump! In later years, I had a 29 and a 37 with UGFs but those were run with powerheads, and also had HOBs running too.
What size tank? Eight years ago, I upgraded to a 75 gallon, with 2 (full bottom) UGF plates, each run with a powerhead, and a HOB. Last year, I removed the UGF and powerheads, but plan on putting them back in a few months from now.
What fish you kept? I have always had fancy goldfish (with a brief foray into gold severums a very long time ago).
Type of substrate? Depth of substrate? I have used the same gravel substrate for at least 25 years, Este's Bit's of Walnut. It is about 1/4 to 1/8th inch in size. Depth was usually about 1 and 1/2 to 2 inches.
Maintenance you did (method and how frequent)? With the smaller tanks, I did PWCs with a basic gravel cleaner and a bucket. I made sure to go straight down into the gravel and hold it there until the water being sucked up the tube ran clear. Then straight up and over to the next spot. I did the same technique with the 75 gallon, but I upgraded to a python. I always did the whole bottom of the smaller tanks at each PWC, but with the 75 gallon I did half of the bottom and did the other half at the next PWC.
How long you used the UGF? The longest I have used a UGF continously would be on my 75 gallon. It was in place for 8 years and was not pulled up at all during that time. If you are asking when I used a UGF for the first time, that was in the early 1980s.
Why you got one in the first place? As mentioned above, it was the only style of filter that I could find that would fit into a cookie jar. And then I just kept on using different version with later tanks. I eventually discovered that they work much better with powerheads, and even better with a HOB running at the same time.
Any training or research you did to know how to use them? Just time, and observation.
Method of testing water parameters? No testing at all in the early years...did not know any better. But I had a part-time job at a fish store in the late 1980s, and was introduced to the concepts of testing and the nitrogen cycle...finally!
Frequency of water changes? Currently, 75% monthly, cleaning half the gravel via python each time.
Did you have live plants? With goldfish? No! :lol:
Did you even attempt them (live plants)? Once, huge mess, clogged HOB, never again!
What plants? What fertilizers?
Anything else you can think of that would be helpful or pertinent? In my humble opinion, a UGF MUST be run with a powerhead on each plate, and a good strong one at that. I have never had a large cloud of debris released when pulling up a plate, and am puzzled when I read about that happening. There was some crud released when I pulled up the plates in the 75 gallon last winter, but it was not much at all and the plates had lain undisturbed for 8 years. The tank that I had before the 75 was a 37 gallon (same footprint as the 29 gallon I had before that) and it was on an open wrought iron stand. I could kneel on the floor and look up at the underside of the UGF plate. Even after about 6 years of undisturbed running, there was only a small amount of crud built up in the front corners. The rest was clean as a whistle.

The best part of a well-powered UGF for me is that the poop gets quickly pulled down into the gravel. Goldfish poop alot, and I hate seeing the strings laying there until they dissolve, or get blown to the cannister. When I removed the plates (thinking that my new Eheim would be plenty for the tank) I was amazed and dismayed at the difference. And that is why I will be replacing the UGF system when I get the time to do it, probably this upcoming winter.
 
Well its about time I add my own experience to this thread. I am posting this now, because, as of yesterday we no longer are using UGF's on our tank... I'll give the basic info, then the story as to why.

What type/model did you have (risers with airlines/air pump, power heads, etc.)? Airlines and risers.
What size tank? Tank is a 20 gal high
What fish you kept? Guppies, glowlight tetras, Black kuhli loaches, ghost shrimp
Type of substrate? Depth of substrate? Black gravel, (with plates) about 3"
Maintenance you did (method and how frequent)? PWC with gravel vac, between 30%-50% of gravel, weekly, with about 40%-70% of water.
How long you used the UGF? 4 months
Why you got one in the first place? Came with the established tank we bought
Any training or research you did to know how to use them? I actually did pretty extensive research on them online. I read just about every article and thread/forum I could about them.
Method of testing water parameters? We had test strips until just recently
Frequency of water changes? weekly.
Did you have live plants? Wisteria, anacharis and amazon sword
Did you even attempt them (live plants)? yes
What plants? What fertilizers? no fertz
Anything else you can think of that would be helpful or pertinent?
Now to the story as to why I got rid of our UGF's. We bought an established tank in may, and it came with UGF's as the only filtration. We quickly added a HOB filter, but left the UGF. After doing some more research we realized that there may be a build up of sludge underneath. We pulled all the fish out, removed the gravel, and sure enough there was ALOT of sludge. We cleaned it out, and put new gravel in (we didn't know enough about cycling and the N cycle to know better). I was determined to make the UGF's work. I emailed several people who had used them for years, and asked for their experience,and read everything I could online.

Yesterday I was doing some deeper cleaning than my regular weekly cleaning. I siphoned out 1/2 the water into a large plastic bin, removed most of the decorations, and most of the fish (some are just too hard to catch to make it worth trying). I had disassembled the risers on our UGF's to clean the inside of the tubes. I use a cheap baby bottle brush. when I put the bottle brush into the section of tube connected to the plates/grids a large mass of sludge came back out with the brush. I have been very careful to clean my gravel often, and have tried very hard not to over feed, yet here was this huge mass of sludge under my plates. And this is only three months after I pulled them and cleaned them. Besides being very worried for my fish (sludge in the main water column = possible ammonia spike) I was very disappointed and disillusioned. I quickly removed the rest of the fish and decorations to the temp holding bin, and added the hob filter to the bin.

I talked it over with my wife, and we decided to pull the UGF's. I don't want to deal with the sludge and work any more. So out came the gravel, out came the UGF's, and the tank got a major vinegar scrub down and rinse with the hose on the front lawn. We went out and bought some pool filter sand, and an Aquaclear 50 to replace the UGF's.

I won't say that you can't make a UGF work, but I think its a lot of work. I had been toying with the idea of getting some reverse flow powerheads and trying it that way, but yesterday.... well maybe down the line when I have money to play with and not have it matter I will experiment. For now I need a stable tank that I can have some level of confidence will not be a ticking ammonia time bomb.

Sad thing is that I had some wisteria growing VERY well in the gravel with the UGF. Though I now suspect they were getting all the nutrients they needed from the sludge underneath.

Well that is my experience with UGF's. Hope it helps someone else learn and make a wise and informed decision.
 
I have been waiting for additions to this thread, and your contributions confirm some of my beliefs when it comes to UGFs, so thanks!

What type/model did you have (risers with airlines/air pump, power heads, etc.)? Airlines and risers.
Yup, right here I knew your experience was not going to be positive...UGFs can NOT (in my humble opinion) be well run with air power. You must have hefty powerheads going.

Type of substrate? Depth of substrate? Black gravel, (with plates) about 3" Too thick (maybe) for even a powerhead, way too thick for air power. VERY little water (if any) was getting pulled thru the gravel, and circulation is critical for a UGF to work.

Did you have live plants? Wisteria, anacharis and amazon sword
I have never tried live plants with a UGF but I suspect they will be a bad idea as the roots will clog up the slits in the plates.

Anything else you can think of that would be helpful or pertinent?
Now to the story as to why I got rid of our UGF's. We bought an established tank in may, and it came with UGF's as the only filtration. We quickly added a HOB filter, but left the UGF. After doing some more research we realized that there may be a build up of sludge underneath. We pulled all the fish out, removed the gravel, and sure enough there was ALOT of sludge.

I use a cheap baby bottle brush. when I put the bottle brush into the section of tube connected to the plates/grids a large mass of sludge came back out with the brush. I have been very careful to clean my gravel often, and have tried very hard not to over feed, yet here was this huge mass of sludge under my plates. And this is only three months after I pulled them and cleaned them.

Sad thing is that I had some wisteria growing VERY well in the gravel with the UGF. Though I now suspect they were getting all the nutrients they needed from the sludge underneath. (Yup, poor circulation equals sludge!)

QUOTE]

If you do try a UGF again, I will be interested in your results, especially if you get some serious powerheads going, with less gravel (maybe 2 inches max). Thanks again.
 
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