Does any one know what size filter should be used for an 81 litre tank with goldfish?

Answer 1

The sizes the boxes recommend are more for smaller tropicals and not the very messy big goldfish so don't go by that. For goldfish it is usually recommended to have a filter that pumps the water 10x per hour. So for your tank the filter should do no less then 810 LPH but more is always better. In my tanks I aim for at least 15x per hour. If the flow is too strong you can either turn the flow down on the filter or add plants or other decorations under the flow to break it up but it should be fine unless the fish is sick and weak.

Answer 2

81 litre tank is only about 22 gallons, i hope you dont have more then 2 baby-juvenile fancy goldfish OR 1 longbodied goldfish in that size tank.

When getting a filter for goldfish it is recomended to go 1 step higher on the filtration then is recomended for the size tank. For example i have a 30 gallon tank, and a whisper 30 filter is recomended for the tank, so i go for a whisper 40 if i had goldfish.

Answer 3

I am of the opinion that the more filtration the better, especially with goldfish because they produce a lot of waste. I personally like the in-tank filters because I can push the fish tank completely against the wall. The biggest in-tank filter that I could find was for a 40-gallon tank so I bough two and put one on each side of the tank. I have found that this works great and that I really don't have to change the water as often.

When you to the store to look for the filter read the label it will say for what size tank it is intended. With goldfish you really need to get a filter that is intended at very least for the size of your tank and if your budget allows for more get nthe biggest that you can afford. I hope this helps.

Answer 4

Go with a filter that fits the aquarium,just remember,a filter doesn't do any thing but take the poo and garbage out of sight,it's still in the tank and it's still in the water. Imagine, if you will, that you and your whole family, and maybe a few strangers thrown in for good measure are all living in one room. In one corner is a big plastic box,no lid just a box. Nobody can leave and everyone poops in the box then if there is uneaten food that would go in the box too.How often would you like to have someone empty the box? Would a great big box that will hold a lot of poop be a good idea? How would you feel about extra food? My point is, just because we can't see it doesn't mean your fish can't tell it's in the poop box. A great big filter might make life easier for you but it's really not doing your fish a favor.Good luck,to you and your pets,and don't waste money on an extra large filter. Hope this helps.PeeTee

Answer 5

I would suggest a filter with a minimum pump capacity of 400l/h to a max of 800l/h, that means it can cycle the amount of water in the tank from 4 to 8 times. I know the l/hr I gave is higher, the reason is that filter performance drop once, media is added into the filter and as waste accumulate the filter or pump performance drops further .

Anyway too strong a pump capacity will cause your tank to become a whirlpool :) I doubt your gold fish would appreciate that.

Also find one that support both mechanical and bio-filtration. That mean it have place for sponge or wool to trap solid fish waste and un-consume food and space for bio-media like Ehiem substrates where good bacterial can live.

Answer 6

get the largest you can afford that will fit. goldfish produce alot of waste. make sure you have the foam, carbon (black charcoal stuff) and an ammonia filter cartridges in there

Answer 7

get the biggest available for you