I have no idea, they all look the same to me. I used to have a pair of those shrimp living with a pair of
it is tenuous at best. held 2 snails for a month or so though. till it got cold. Might try a goldfish in it next. they're cold tolerant...(I really hope I don't need to say I'm joking. But in the event that someone takes me seriously, you are wrong in that, it's a joke.)Increasing biodiversity is always a good thing, but with a tank that small one pod may tip it over the edge.
Back in the early 80s I had 2 Mostly FOWLER tanks, a 55G and a 135G, both with normal flow UGFs. The 55 was closer to a reef tank, with a few corals and metal halide lights. The 135 had larger predator fish, a Lion, a Panther Grouper and a couple morays.
The flow isn't enough to push anything up. It just keeps flow going in the plates. Too much flow would be a bad thing. I have a 250gph supplying my 90g I think.
Reminds me of the "tufa rocks" that were available in the 00's. I havent seen them for sale anywhere and they were a great rock, lighter and more porous, and cheaper, than the dry rock available now, kept the ph buffered and didnt leach anything.
OK, so what happens to the detritus, uneaten food etc? If it just lays on top of the substrate, it'll be "processed" just the same as in a regular flow UG, right?
I fail to understand how that is different from a normal flow UG. Both tuned correctly will process those organics to prevent clogging in either direction.
My point isn't that the RUGF isn't useful/valuable, just that there's no great premium for reverse flow as opposed to normal flow.
Its not true - right done it can be an excellent denitrification tool.
John, don't feel bad, I am not sure exactly how or if it works better, but from plenty of experience I know it does. As I said the regular filter kept crashing and clogging. I am not sure why but it could have been I was much stupider then and either fed to much or the wrong food.
I'm confused; what does ethanol dosing have to do with the difference between regular or reverse flow UG filters. I use vodka dosing in a tank w/o an undergravel filter and it works great in the water column. I'm confidant it would work great in the plenum also. My question is, so what?
The fact that hardly anyone uses UG filters in the regular flow way isn't much of an argument when you consider that almost no one uses them anymore in reverse flow either. I can't compete with your 40 years of success with reverse flow, but as I said I'm not arguing that it isn't a good idea or won't work or is inferior to regular flow....
But when it ran normally it didn't last long. You need to do an experiment with a regular UG filter running it about 25 years to see if it lasts that long.
There is a reason virtually no one uses them that way.
followingSomeone asked me how a reverse Undergravel filter works and what is the advantage of it.
In the beginning, when we all kept bait, I mean fresh water fish we all ran undergravel filters. That was the only way to go and in fresh water they work perfectly.
When salt water started for home tanks in 1971 in the US (a little before that in Europe) some of us switched our tanks to salt but we kept our UG filters. Most of us did change the gravel to something different than the purple broken glass we had in fresh water and we removed the sunken chests and deep sea divers fighting sharks but there was no salt water gravel available.
After unsuccessfully using blue driveway gravel I discovered dolomite. You can still get it at a mausoleum or museum, maybe an archaeological dig in Egypt, I don't know but I assume crushed coral would also work.
I first ran my salt tank using a normal UG filter and in less than a year it crashed and I had to rescue my fish. There was no coral, live or dead rock then but we did have bricks, cinder blocks and roller skates. Much of my "rock" was asphalt that was dumped in the sea before I was born. I still have some of it and if you look close you can probably see remnants of the yellow line that was painted on it when it was a street.
I am not sure what the problem was by using a UG filter the normal way. We didn't have powerheads so they were all run with bubbles and they didn't run to fast but the salt creep on the lights caused us to have to turn on the lights with a stick because GFCIs were also not invented. As a matter of fact, to do anything on the tank we had to unplug everything and the only thing we could keep with success was electric eels.
Anyway, the UG filters, after a few months became totally clogged rendering them useless similar to some politicians.
I decided to reverse the thing and instead of the water going down through the gravel, now it came up through the gravel. Something happened. It was a good thing. The tank didn't crash. It kept going and fifty years later it is still running.
Not crashing is a good thing but not the only benefit. I learned from Robert Straughn "The Father of Salt Water Fish Keeping" that the bottom of the tank is the perfect filter and the largest thing in the tank. Mr. Straughn used UG filters constantly but at that time, in the 50s he didn't quite understand the function of bacteria like we do today and he used the filter as a particle filter.
That works but you have to clean it constantly and as a whole, humans are lazy.
I discovered that if you pump water through the gravel at a slow speed and maybe strain it of particles first, the thing would not only last forever, 50 years anyway, but the tank would thrive and it would be easier to keep smaller fish.
A sand bottom has very little oxygen going through it as it is stagnant. But gravel, even if it is just sitting there has water flowing all through it. But if we give it a little help and push a little water through it, multitudes of creatures colonize it causing it to be a huge eco system.
Tiny tube worms, brittle stars, pods and bacteria completely fill every void. Those tube worms filter the water and the brittle stars remove particles. Very little detritus is left and a little detritus is good because it even provides more living space for those creatures which hate clean, sterile places to live sort of like Ozzie Osborn.
Those tiny creatures can breed in multitudes feeding smaller fish like pipefish, mandarins, dragonettes and anything that eats pods. I have many of those fish, they are all spawning and I never have to feed them.
This silly thing is the manifold I used for many years. I built a new one now but it is the same principal.
It is of course an old HOB filter. The three tubes coming out the bottom go to each of the 3 UG filter tubes.
The one on the left doesn't do anything and was a mistake, it is blocked.
Water is pumped into the thing from that hose on the left. I don't have a sump or I would have to divert some water from that to here.
I run about 250 GPH down each tube so about 500 GPH is pumped into the manifold where the water is evenly separated. Faster flow is no good, it has to be slow.
Once or twice a year I stir up the gravel where I can reach with a canister filter or diatom to remove excess detritus. If it was left forever it would probably clog eventually and besides, I like doing it.
Of course if your present system lasted longer than fifty years, do that. ;Joyful
I can only prove that it can run for 53 years with no problems. I can't prove a regular UG filter can run very long because mine never ran very long. But in the early 70s, no one could keep anything alive, not even mojano anemones and we used to feed them to try to keep them alive.
Because you get the denitrification where it should be - in the bottom. DOC (Dissolved Organic Carbon - in my case pure ethanol) is required in the anaerobic metabolism as electron donors when NO3 is used as an electron acceptor in the absence of oxygen - Waste here is N2 and CO2. You get a very effective and concentrated denitrification and does not need to fertilize the water column with DOC and therefore avoid too strong growth of oxygen-consuming heterotrophic bacteria in the DT.
