Filtration On Goldfish Aquarium

Galathiel

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Background: I have a 46 gallon acrylic bowfront aquarium. It has a permanent top with rectangular cutouts to access the tank (yuck). Currently running a Fluval 306 canister. I have 2 orandas that are probably 5 inches tip to tail and 1 much smaller blind telescope (probably 2.5-3 inches tip to tail).

So, I really like my canister. It's a nice thing. The problem I'm having, I think, is that I interrupt the output because of the current it caused that pushed my sand to once side. What that has done is really prevent some of the floating particles and detritus (mainly goldfish poop and bits of leaves from their fresh veggies) from being swept to the input. It really shouldn't look this nasty all the time and I think it's because of insufficient flow. I'm worried about upping it .. how that will effect the goldfish (okay swimmers, no issues, none have buoyancy issues, one is blind). I can't add a HOB because I can't move my aquarium out from the wall due to the location. There's only enough room to run the canister hoses up the back. Just up the flow rate on my canister and see what happens? Right now I have a silk plant hanging from the heater (ghetto) and the output hits that. I also have adjusted the flow rate on the canister itself to about half way.

For those that have sand, what do you do about the sand getting swept to one side of your aquarium? Do you even have that issue?

Is this enough filtration for my aquarium?
 

Notivation

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Goldfish, as you are probably learning, are mega waste producers and can live forever growing to massive sizes. The general rule of thumb is 20 gallons per fancy gold fish, and 50 gallons per 'regular' goldfish. In all honesty, I would think it best just to have an outdoor pond dedicated to goldfish if you want to keep them at all. If you're going to try to keep three in a 46g, I would make sure that you have the maximum amount of flow through your filter possible, and maybe even set up two canisters.
 

Swampgorilla

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I would not restrict the output flow of that canister - instead, I would custom-build an output for it. You can easily build your own pvc spray-bar - thats curved, and runs along the inside top of you tank along the back. OR - you could easily build a PVC output that runs down into the water and diffuses the current flow.

Here's how I diffuse TWO canister filters on my "pond-tank" for goldfish ...


So it can be done.

And no - you do not need a lot of current to sweep your poop into the filter intake ... although I would put the intake as low as possible in the tank to make big water changes easier and to catch the stuff that floats around on the bottom.


And yes ... goldfish are very dirty and it's very hard to keep the tank clean ... you'll have to do a lot of vacuuming. I would recommend buying one of those handheld Eheim things that are battery powered if you don't want to break the Python out every day.

I have sand ... CoribeSea Torpedo Beach ... but not in my goldfish tank - that's in the cory catfish tank.

I switched to a bare-bottom tank for the Goldfish. Much easier to keep clean (it's pretty much immaculate) and keep bacteria and parasites down.

Do you have enough filtration? Well I personally think you have enough FLOW ... but I don't know how much bio-filtration a Fluval 306 will hold ... or how much you have in it.

EDIT: As far as your tank size. You can keep three fancies in a 46 but, imo - you will be changing water a lot unless you plan to live with high nitrates. But if you intend to keep them below 20ppm (which is what I recommend) ... you will be changing water probably every two or three days ... and BIG changes too.
 
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Galathiel

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There are several 'rules of thumb' when it comes to goldfish. Very much debated lol. I went by the whole '20 gallons for the first and 10 gallons for each subsequent' camp.

The Fluval 306 has three baskets plus a side portion that has horizontal rough sponges. It holds a lot of media. It has sponges in the bottom, almost 2 boxes of biomax media in the middle and some more in the top basket, along with some quilt batting. The intake is a few inches above the sand to make sure it doesn't pull sand into the canister. However, I'm able to do even an 80 percent wc without issue (I always shut off everything anyway). It's just that the center of the tank seems almost dead (I see particles floating in place almost from their spinach etc).
 

Skye_marilyn

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Background: I have a 46 gallon acrylic bowfront aquarium. It has a permanent top with rectangular cutouts to access the tank (yuck). Currently running a Fluval 306 canister. I have 2 orandas that are probably 5 inches tip to tail and 1 much smaller blind telescope (probably 2.5-3 inches tip to tail).

So, I really like my canister. It's a nice thing. The problem I'm having, I think, is that I interrupt the output because of the current it caused that pushed my sand to once side. What that has done is really prevent some of the floating particles and detritus (mainly goldfish poop and bits of leaves from their fresh veggies) from being swept to the input. It really shouldn't look this nasty all the time and I think it's because of insufficient flow. I'm worried about upping it .. how that will effect the goldfish (okay swimmers, no issues, none have buoyancy issues, one is blind). I can't add a HOB because I can't move my aquarium out from the wall due to the location. There's only enough room to run the canister hoses up the back. Just up the flow rate on my canister and see what happens? Right now I have a silk plant hanging from the heater (ghetto) and the output hits that. I also have adjusted the flow rate on the canister itself to about half way.

For those that have sand, what do you do about the sand getting swept to one side of your aquarium? Do you even have that issue?

Is this enough filtration for my aquarium?
I am not specifically acquainted with the fluval 306 canister but I know for sure fluval is notorious for lying about capacity and gph. Going forward I strongly recommend upgrading to something more stable that will last longer like a filstar hooked up to an FSB filter, some FSB filters can handle up to 20 lb of waste at a time. I also agree with @Swampgorilla and think you should purchase an Eheim sludge remover to keep DOC under control. Make sure to clean your filter every 3-5 weeks to avoid it becoming a nitrates factory. You could try hooking up the outflow on the opposite side of the intake to get different directional current but I’d play around with it. I think keeping the intake lower than the outflow is a good idea. You also may want to consider purchasing a true level one UV sterilizer in line with your canisters if you are having bacterial issues. If you place the UV in line with a power head or internal filter you may be able to achieve a more even and directional flow.
 
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