Pond Filtration

[Ozy]

Hi there. Looking for some advice tips on good affordable pond filters. The pond is approx 450ltrs. The filter will be placed above the pond where the inlet will shoot the water out and create the waterfall. I’m also thinking of having filter media within the waterfall structure too. The pond will house 10 - 15 gold fish and a few plants in pots. Furthermore, the pond gets plenty of sunlight. I’ve had huge algae problems with it before, looking at ways to minimise this as well. I Would like to know the good filter brands out there. Thanks.

 

[Sharpchick]

Hi there. Looking for some advice tips on good affordable pond filters. The pond is approx 450ltrs. The filter will be placed above the pond where the inlet will shoot the water out and create the waterfall. I’m also thinking of having filter media within the waterfall structure too. The pond will house 10 - 15 gold fish and a few plants in pots. Furthermore, the pond gets plenty of sunlight. I’ve had huge algae problems with it before, looking at ways to minimise this as well. I Would like to know the good filter brands out there. Thanks.

450 liters is approximately 118 US gallons. You need a filter that turns total pond volume over twice an hour.

And 10-15 goldfish in that size of a pond is way too many - even fancy goldfish, never mind comets, commons and/or shubunkins.

Algae in a pond is food for the fish. One of your "problems" with algae is "a few plants in pots."

You need two to three bunches of submerged stem plants per square foot of pond surface area, plus any potted plants you want to have.

As to affordable pond filters, after doing research all last winter, I found that for capacity alone (but not as the sole factor), a bog filter was the least expensive way to go.

 

[Ozy]

Hi Sharpchick, thanks for your reply. I was initially going to dirt the pond with dirt and laterite. Also some crushed coral to maintain 7ph - and not have the pots. I can spread the plants around easier this way. Would the crushed coral be ok - of course everything will be capped with some sought of gravel. And how many fish should i house? Im from melbourne australia. It never gets too hot or cold here. I will check the bog filter out. I just want to minimise the algae as in the summer it covers half the pond.

 

[Sharpchick]

Submerged stems need no substrate. For lilies, rushes and other marginal and mid-level plants, you just plant them in the pot. You would need very deep substrate to accommodate the root system of a hardy pond lily or lotus, and that would decrease the amount of water in the pond, necessitating a lower stocking level and hotter water in the summer.

I have no substrate in my pond. If you are using a pond liner, I'd have a hard time seeing the need for a substrate.

Is your water uncommonly acid? Why do you feel the need for a buffer? Ponds being larger than aquaria and outdoors are generally much easier to keep stable than indoor tanks, but not if the pond keeper is constantly fiddling with the pond.

The number of fish depends on the kind of goldfish you want to have. Plan on 50 gallons ( ~180 liters) per for comets, commons or shubunkins, half that for fancy goldfish.

If you have a temperate climate without many temperature swings, you could probably house fancies year round in your pond.

ETA: Make sure you have lots of floating plants in the pond. They help regulate temperature, combat algae and increase oxygen available to the fish. Common floaters include water lettuce, water hyacinth (where legal), azolla, salvinia minima, duckweed, frogbit, etc.

 

[Ozy]

Thanks sharpchick, I will place three pots only. My pond was built many years ago using pond concrete. Unfortunately we have many gum trees towering the pond. So I get a lot of leaves all year round which acidifies the water. I have in the past cleaned it out using nets – however in addition I will need a pond vac - if there is such a thing. So as to clarify the amount of comets – 1 per every 180litres. 450/180 litres = 2.5 seems very low – but I understand they are very messy fish. What ever makes them happy - that’s utmost goal. My brother inlaw was going to build a pond last year but never did. He has a 3000ltrP/hr and a 2000litreP/hr filter with uv light. The filter is called a Biologic 4000uvc. He may give this to me.