How Do These Fish Thrive? No Gravel Cleaning?

[ParrotCichlid]

Seen a display tank in a shop a few days ago. The tank looked about 20g in size.

It had about 50 fish or more in it. Every bit of open water was filled with a fish. It contained many different species of barbs including tin foil barbs. It also had loads of plecos in and apparently the store breeds plecos in this tremendously overstocked tank.

What is more shocking is that the guy who maintains it never vacuums the gravel. He simply replaces about 5g of the water tgat evaporates each week and thats it!

All the fish look very healthy and no obvious signs of stress. The shop worker convinced me that the water quality stays great.

How is it functioning?

How can the water quality be fine with no gravel vacuum use?

I done a little experiment on my 10 inch zebra tilapia tank a bit ago. I dodn't vacuum the gravel for close to 2 months. All i done was drain 50% of the water and replace it every 10 days or so. The water quality never changed!

Will upload some pictures shortly

 

[OneLittleBubble]

very big filters and though you may not see it I bet you 100% at least 5 of them die every day you just don't see it because they are good at making the tank look clean.

 

[ParrotCichlid]

very big filters and though you may not see it I bet you 100% at least 5 of them die every day you just don't see it because they are good at making the tank look clean.

Interesting opinion. The tank definitely does not have superb filtration as its in the middle of the checkout desk. Looked to be run on just internal filtration. They did have lots of aeration with pumps.

Well the guy has agreed to freeze all the dead fish they get in each week for me carnivorous fish food for my predators. So i will sure know if i get a bunch of dead barbs on Monday.

But its not the first tank I've seen like this.

My guess is that all the junk simply gets trappef in the substrate (As they don't gravel vacuum) so providing the gravel osn't desturbed thwn it probably wouldn't change the water quality a great deal. Of course if you gone and vacuumed that tank months later it would probably send parameters all over the place.

Opinions?

 

[Biev]

I guess it could be done with enough bio media, a cleanup crew and plants. I doubt they're really thriving in there, though.

 

[Mcasella]

Fish can handle some extreme parameters of they are adjusted to them over time. Hence "old tank syndrome", where the fish can go into shock when new clean water goes into a tank that is not used to it.

 

[david1978]

I do monthly maintenance on my tank but im really understocked. If i go to 2 months i start noticing changes to my water conditions. No rise in ammonia, nitrites or nitrates but my ph starts to go down, dissolved solids rise and dissolved oxygen goes down. Granted it not a whole lot of a change but i would assume as time went on the trend would continue and would reach a point in probably 8-10 months that it would so very different from my tap that an emergency water change for whatever reason would shock the fish.

 

[Dreypa]

Was it heavily planted? If so that could contribute to a little less maintenance but not to the accord of almost 0.

I agree with parrot on the lines of most junk getting stuck in substrate and not being disturbed. My father got away with not gravel vacuuming in his goldfish tank for years. Only lightly kicking dirt up with his hands in a blue moon. Once I inherited the tank and performed regular gravel vacc'ing parameters were a bit janky afterwards. One of the goldies definitely was not used to regular water changes and deteriorated his health from it.

 

[ParrotCichlid]

No the tank was not heavily planted. I don't think it even had a living plant in it.

I'm going to test this theory on my new 14g tank.

Don't worry, I'm not going to cram hundreds of fish into it lol but what I'm going to do is not gravel vacuum it whatsoever. I will monitor the parameters every week and lets see what happens.

I think the very reason we don't get a good bacterial colonization in our substrates is because we gravel vacuum them. Inevitably removing BB on each run. So i have this feeling that if you never gravel vacuum then you get a much stronger colony of beneficial bacteria. Probably strong enough to break down most fish waste and uneaten food in the substrate.

The tank will still get 50% weekly water changes but they will just be removing water with a pipe no gravel vacuuming.

Will be interesting to see how this turns out. Of course if parameters start to go off i will abort the experiment.

I don't mind making a post to document this on here if anyone is interested in the out come?

 

[WadeEH]

No the tank was not heavily planted. I don't think it even had a living plant in it.

I'm going to test this theory on my new 14g tank.

Don't worry, I'm not going to cram hundreds of fish into it lol but what I'm going to do is not gravel vacuum it whatsoever. I will monitor the parameters every week and lets see what happens.

I think the very reason we don't get a good bacterial colonization in our substrates is because we gravel vacuum them. Inevitably removing BB on each run. So i have this feeling that if you never gravel vacuum then you get a much stronger colony of beneficial bacteria. Probably strong enough to break down most fish waste and uneaten food in the substrate.

The tank will still get 50% weekly water changes but they will just be removing water with a pipe no gravel vacuuming.

Will be interesting to see how this turns out. Of course if parameters start to go off i will abort the experiment.

I don't mind making a post to document this on here if anyone is interested in the out come?

Yes, please keep us posted. I would like to know what happens.