I have ugf in my 125 gallon tank. 6 inches of gravel. Water is crystal clear and needs no cleaning. Full of live plants. Deep gravel is the key to creating a system like mother nature did.

Great info Doc. I've been running UGF for as long as I been in the hobby since the early 70s. I also have several antique tanks with the slate bottoms that were my grandfather's that all run ugf and the little plastic box filters. In my entire Fishroom of 47 tanks from 5 -310 gallon tanks I will say that my tanks that run ugf (38 of them) are the most stable and clearest tanks, I run them on air with an air diffuser in the lift tubes. The larger tanks even have a diy ugf in them with 4 uplift tubes, I will admit that the large tanks I run power heads, and several hob due to the size. Plants grow like crazy in my smaller tanks, even tho I've heard for years they won't grow. I'm getting ready to set up a couple tanks using your system. To me I think the reason they fell by the wayside was manufactured figured out that they wouldn't make money because they worked so good. Always learn something from your vids. Keep the info coming . My local mom and pop store still advise the use of them and will even offer them to new customers buying new tanks.

Love the blast from the past ads

I can see why manufacturers started trying to make them "bigger and better" over time. It's a trap we all sometimes fall into think more flow is better somehow. Funny, my first ever aquarium was a really old 20 aquarium given to me for my pet turtle that came with an old hang on back filter and and undergravel plate. The uplift tubes were missing so I never hooked it up, just ran the hob filter with some dirty pillow stuffing I was too inexperienced to know needed changed more often, whoops (I was only 9 years old) lol. My water despite having a messy turtle was always very clean and the gravel wasn't a mess when he dug around through it. No bad smell, nothing! I really appreciate your content and spreading your knowledge and research while making things easier for us hobbiests to comprehend.

I used them through out the 80s and started added them to my current tanks

I have used UGF’s since the 70’s. I never had any problems and my tanks worked great. You are right about what happened with larger uplift tubes and more increased water flow. The manufacturers didn’t have a good reason to change a design that worked perfectly. I still use UGF’s to this day and they work perfectly if you know the correct way to set them up. 👍 A great walk thru the history!

Had aquariums in the early 80s and they worked great. I started up again recently and I am using them again. I'm going with what I know truly works well no matter what they say.

Dr. Novak, it seems that manufacturers didn’t understand the biology of the slow flow under gravel filter. Hence they changed the flow rates and other things over time. I do remember in the early 80s being told I needed high flow from my lift tubes off my under gravel filter. Time makes circles thankfully and we’re back to getting good biologic function.

I've been running tanks since the late nineties and I've found the original under gravel filters are very good for the plants by moving nutrients around the tank but bottom feeders hate them for stealing food. My tank that has done the best has ugf on only half the tank.

Hi Dr.Novak! A walk down memory lane. 🙂Well I am old enough to have bought brand new and used under gravel filters. I got my first tank, a meta frame, brand new from KMart in 1975 as a 4th grader who loved nature. This was very interesting as to what happened on the marketing side. I think another factor was a "germ phobia" as well. There was not much knowledge, at least among the general public, about beneficial germs aka bacteria. I remember my mother making me take the fish out into a bucket, pulling all the gravel out and washing it, cleaning the entire tank as though surgery was to be performed in it because "germs were bad". Of course after doing that and putting all the fish back most died from the ammonia spike. So not only was it a lot of unecessary work, the death of my fish discouraged me. But you know what, the old school under gravel filter worked just fine if left to do it's job!! --in edit-- Sorry this is so long! You really got me thinking - in the late 1980s as a young adult I got back into the hobby because of "biological" filtration (as a marketing term). Marineland came out with the HOB with Biowheels. I decided to try it and keeping fish again. I was successful! I didn't have to "scrub" the substrate. Naturally I attributed that to the biowheel and started learning about the good "germs"! It's been a long journey as a lay person. All I can say is used properly both the under gravel filter and the aerobic systems have worked in my low tech, lightly planted systems over the years. I gauge the success of my tanks by fish life longevity, reproduction, color and growth. BTW - I think an interesting topic to tackle would be the commercial fish distribution system, especially from large ornamental fish farms that heavily use hormones and antibiotics and then send weakened fish to the home aquarist. In my opinion that is the biggest problem in the hobby right now. When people new to the hobby have fish die, they get discouraged and leave the hobby.

I recently bought a 13g aquarium from a mom and pop store that has a under gravel filter with 3" of gravel on top. I love how it just works. My guppies love the tank. Never had a hiccup.

Started keeping an aquarium in the early 70s with the small corner filter. After that, graduated to undergravel filters and had great success with them. Now, thanks to you, I’m back to using undergravel filters but with the anoxic system of low flow etc. Everything working beautifully and am enjoying my aquariums. Thanks!

Back in the late '90s I was a teen learning how to run my aquarium from library books. It seemed so much easier and logical then. I had pretty good success even with the undersized UGF that came with the second-hand tank I had. (The thing that killed my goldfish was excessive heat and I had no way to keep them cool in the summer.) After a break of 22 years or so I return to fishkeeping and find it seems so much more complicated and expensive if you buy into the modern way of doing filtration. Thank you for your videos and good explanations of the biological processes needed for a healthy aquarium. Incidentally, the best success I've had with goldfish was in a pond where they were all but forgotten about.

Great video. I never had understood why undergravel filter had gone away from the hobby. I kept fish up until the mid 90's before taking a long hiatus. I made my return back to the hobby in 2013. Everything had changed. Canisters were the supreme filters and undergravel filters were evil. Soon, I realized there was nothing wrong with my old filters. Then I found you and my hobby is back to being pure enjoyment.

I remember my first tank had the green under gravel filer . this was back in 1985 .

Hi Dr Novak, I've just found your channel. I'm a massive fan of 'old school' fish methods. I have recently set up a dirted tank capped with moler clay cat litter. I really like the idea of setting up a plenum.

Still using my under gravel filter in my 55gallon along with a HOB, two filter's are better than nothing! I have had them since the mid 1980's.

I used a ugf in the 90s with a very fast running pump and full height lift tube. It never worked and used to wonder why this filter exists. Now I have plenums like you suggest and i see very less dirt in an overstocked cichlid tank 🥳. Thanks 🙏

Yes I agree 100%, used them in 70-80s and loved it! Infact getting ready to start up a new 70 gal. and as part will be going back to the under gravel.

What I have learned from you is slow and steady wins the race. These things work and work well. Thank you for the information. Oh a side note on November 4th I set up a straight undergravel filter with a 4" pea gravel substrate (no kitty litter, laterite or BCB baskets) for a 46G bowfront I tested weekly for 3 weeks and nitrates have stayed low and tank had started diatom stage in 7days and is always clear.

I had an under gravel filter in my tanks in early 90's. Water was always crystal clear and I was a kid so yeah, I didn't clean it.. ever.

I've been running a plenum on my 10G tank since September, I intentionally left 3 sides of the UGF uncovered, and in this 4 months that the plenum has been running I haven't find any build up of mulm or anything weird, just a bunch of roots growing in the plenum area, the plants that I am using keeps growing and my shrimp breeding, so far I am satisfied with it.

Thankyou Dr. for opening our eyes. Thanks again for sharing your great long experience.

Thank you Dr. Novak for always telling the truth.

Thanks Dr Novak for the excellent information & history of the undergravel filter. Yes I agree with you. At that time when power heads came on the market my local fish store said undergravel filters just accumulated dirt and unless you emptied & cleaned the tank frequently the dirt just accumulated and stayed in the tank while the powerhead was easier to clean out. However, I didn't realize then that all the fish poop was already biologically broken down in the undergravel filter and was just inert mulm and therefore doesn't pose any threat to the fish. I just finished setting up my old 15g tank over the holidays with a 1½ inch high plenum & uplift tube. I have however experimented with putting about 1inch of the clay under the plates inside the plenum instead of over so the water flows slowly through the gravel & plenum and the anoxic water will then flow through the plenum over the clay. I hope this is okay. I will send you a picture of the same.

Back in the early seventies I used to have a pipe undergravel filter along with a small canister filter that was also in the fish tank. I also have a water vacuum which was also operated by the air pump which you dont see these days. The fish I kept then where tropical, I was grateful to a neighbor who lived in a flat a few floors below me who helped me set the tank up. He kept marine fish which where really nice to see.

Started gathering stuff for my first tank 20g. Been watching all your videos, thanks. Going to do a diy plenum.

I used Penn-Plax Undertow filters for over 30 years and NEVER had any problems. I just used the air stones and never jumped on the band wagon of power heads or reverse flow. I also had Supreme AquaMaster HOB filters to polish the water crystal clear. Correct, my tank never had a smell. I'll be using an UGF in my 125 gallon tank I'll be setting up next. If it ain't broke don't fix it.

I feel like there are many things going on. With UGF there isnt anything the hobbyist can do you just ignore it and gravel vac every so often which makes some people feel less involved. I also think that some of the modern filtration methods are marginally better when used under optimum conditions and when folks hear well this one is 2% more effective with constant maintenance and supplies everyone forgets the constant up keep and only thinks about the slightly better.

Excellent!!! I started out that way also. Just a air pump, angel hair & the air box filter. Also on a couple tanks, under gravel filters just air in the late 50’s.

Doc, your ears must be burning, reading my mind, and feeling my vibes tonight! I literally just spent the last 2 hrs researching RFUGF, as I have reverted BACK to using UGF's in a slow-moving plenum capacity after watching all your videos for the past year. I am getting ready to set up another divided 10 gallon tank for bettas I have coming in from Indonesia in January. I already have a divided 10g setup with an air flow controlled lift tube on one side and a small AIO filter setup on the other. The lift tube belches out a couple of bubbles every 3 to 5 seconds. The AIO pump flow is set very low as well to just disturb the surface of the water and help circulation, as the tops of the dividers I made are vertically slotted every half inch to allow surface circulation to be less inhibited than the main water column that must flow through the 3/16 holes grid drilled in the divider every inch vertically and horizontally. So the AI0 divider sits on top of the UGF plates, and there is also about an 1.5 of gravel on top of the plate as well. So the AIO pump not only sucks water in through the overflow slots and through the different media chambers, but I would imagine has current coming up through the plenum as well. Then one of the new dual sponge and media basket air driven sponge filters in the middle chamber. Going to set up the new 10 gallon the identical way. I have a 36g set up with a HOB tidal 55 and again a throttled dual up tube UGF. But both up tunes are on one side of the tank. Still have a 75g, 90g, and 125g to set up. Already have a UGF for the 90g, but it's the wavy surface one that I don't think I want to use. But to the point, I was thinking about running a reverse flow in the 90 and 125 because they're going to be black diamond medium grit blasting sand bottom cichlid tanks. But obviously, my cichlids dig. So idk what the hell to do. I know they'll dig down to the UGF grid and screw up the plenum flow, and I'm still not convinced that reverse flow is the way to go, although I've heard that if you're going to use it, that a finer type substrate like the blasting sand is the ideal time to. I am the same as you but a tad younger generation. Born in 1974, got my first pet store job in 1989. The largest fish only store in Nebraska at the time, called "The Fish Bowl." Used to change 10,000 gallons of treated water while vacuuming out 10k gallons of dirty water every Sunday morning from 8am to 10:30am when we opened. I caught the bug way back when and it lasted until I was paralyzed at 25. Just got back into it again a years ago and already have 6 tanks going. I was as surprised as you to see that not only was nobody using UGF's anymore, but blatantly advocating against them. Your points are all true, and I couldn't agree more with what you've been saying and for sure what you said in this video. People are blown away about how clear my tanks are and how. Within an hour of completely dismantling all decor to rearrange and doing vacuuming and filter maintenance, my tanks are back to crystal clear in an hr, and I don't even own a sump or canister filter yet. But I will be buying that stainless brand you're using. Remarkable product for the money. Any way, I don't know what to do about running a UGF in the media substrate cichlid tanks and not having to hassle with the fish creating bare spots and screwing up the flow. Lmk your thoughts please.

Great video. I came back to the "hobby' after many years I belonged to the UGF era and was ""advised" that UGF were a thing of the past and what I really needed this $800 (Australia dollars) cylinder filter plus all these additives. I nearly went down the rabbit hole until I came across your videos. I now use BCBs and kitty litter substrates. It reminds me of that saying that fish lures catch more fishermen than fish. Go into any fish store and look at the amount of chemical products nevermind filters, pumps etc on the shelves. There is money in product because if there wasn't why are there so many out there, and mostly doing the same thing? For example - just look at the range of water conditioners to choose from.

honestly I also think that one main reason people don't like the UGF is because of the lift tubes being visible, when people are trying to keep more and more equipment out of the tank

Marketing is amazing in so many negative ways. Coming back into this hobby after 25 years, I'm amazed how much $$$ people are willing to burn through to grow a 1" coral...

Hi Dr Novak, Thank you very much for the important information . I have an under gravel filter in my aquarium and a small canister filter with 2 bcb bags and some sponges. I also have an internal filter that has a bcb bag in it ( I just added that today ) plus an air stone. I am presently waiting for my nitrates to reduce to below 20. I think they are nearer to 40 at the moment.

We still sell them. As I point out to customers, the only aquariums I don't have problems are the UG ones. On the other hand, I'm always having issues with moving media and pumps breaking on the hi tech systems. The UG is ideal for our South African situation. Spiraling costs and non availability of spares. I've tried every hi tech gimmick since the 80s when the wet and dry trickle system with the rotating spray bar. UG still the best.

i waited til 1 AM for this....i have a 29 gal perfecto UG filter hiding somewhere in the basement. everything old is new again...

I had them in the 70s and because I didn't have enough gravel my plants didn't do well. I then went to power heads and found out the hard way that it was too much flow and got discouraged and stopped for a while. I came back in 20 years ago and still use under gravel and hang on back for mechanical and my plants grow well.

In the 80s I had a 300 gallon with six large tinfoil barbs along with a few other large fish. My conventional UGF was overwhelmed and I was having to do weekly vacuuming which got out of hand. Then I went with a reverse flow setup using a little giant pump and three canisters. The first canister had a pleated filter just like a swimming pool filter the second one had charcoal in a fine mesh bag and the third had a heater in it. I ran this setup for at least 7 years and never had to clean the gravel. I went through 4 little giant pumps during that time. I got a different job that was working me a lot of hours and I couldn't find the time or have the energy to keep up with the care of my fish so I sold it off. Now that I'm retired I'm going to build a 500 to 600 gallon tank and I'm going to use the same reverse flow system. When I get to the point where I'm testing the filter I will let you all know so you can see it in action and how I built it.

My 55 gallon is filtered only by an undergravel filter for the last 8 months. The water is crystal clear, I’ve never gravel vacuumed. The substrate is 2 inches of pea gravel, and 10lbs of lava rock topped by aquarium gravel.

All I use is a ugf and a canister with bcb fzone on the discharge side.

Got a 6ft x 4ft x 2ft tank to set up as I’m upgrading from a 6x2x2. No room under or above the tank so I’m going back old skool under gravel filter. Instead of a plate I’ll be using 40mm solid pipe with holes drilled in them and as it will be for my large marine predators it will be run on a 2500 lph pond pump instead of a power head. Cannot use a big air pump as I will have to much salt creep .

Kodak failed to capitalize on digital cameras they didn’t kill their own company, that was just time.

I don’t actually think they fell out of favour, just the backlash was louder than the supporters. Is still the preferred filter for a lot of shrimp breeders. How much flow is too much?

Please do a video about lighting in the aquarium (how to save money). Thks in advance from Portugal 🇵🇹

Would/should you gravel vac with an established UGF disturbing the debris that accumulates under the plates whether you have plants or not? I have used UGF back in the 70's & 80's in both fresh & salt water tanks with success sometimes using a diatom filter(costly).

Companies figured out they can make $$$$$$$$$$$

does the speed that the water travels thru the polyfill filter floss effect the effectiveness of the filter... i believe that if it flows to fast it works against the efficiency of the filter... notice that these big fast power filters dont really clean the water to be crystal clear like the little box filters do.

Way back i walked into my LFS and asked for two power heads for my UGF. The wise owner asked me why did i need that, is my tank going foul? I said no, i just want to improve my system. Little did i know that guy knew i was wasting my money. I was vacuuming the gravel every week. I should have known because all his tanks had UGF's running a weak air pump. Probably one pump ran the whole store.

would you consider a BOX FILTER with an air stone to be an under gravel filter ?

Can you recommend a UGF for a 20-gallon 24x12 tank, I am just getting back into the hobby after a long layoff.

Ok here is what I would say is an INSANE idea! What if I were to take the Penn Plax under gravel filter (UGF) plates and stacked them? The bottom plates would act like a Plenum then take Kitty Litter and the mixed Iron additive on top then Place the second UGF plates and sandwich the litter Mix, then top it off with normal gravel and put short lift tubes that reach the bottom plates and go through the top plate level with the gravel capped with holes and no bubbler? Or would you think it would need the bubbler? I will have 2 HOBs doing 200GPH each for some Hill Stream Loaches and Danios. I think that would be enough to push the water through the plates even with them stacked. Yeah, Kinda spendy to buy 2 full UGFs but the Kitty litter/iron mix would be off the bottom and protected from a gravel vacuum and you could dose the iron back under the litter in liquid form if needed. I personally wouldn't consider 40-50 bucks for 2 sets of UGFs for a 55 big money, but some folk might. I have dropped 40-50 bucks on HOBs and or Power heads and thought nothing of it. The reason I'm trying to find a way to protect the Litter mix is I don't want live plants and I can't anchor fake ones in the kitty litter and disturb it or run a gravel vacuum. I have considered the BCB bags in a HOB just devoted to them, but I can't get the kind of filter area of a 45"X11.25" UGF and use fake plants. Would I be turning the litter in the UGF sandwich into a BCB basically? Am I over engineering this or is this thinking outside the box?

Capitalism happened. LOL