Re: A pond with tropical fish
#2
I presume this will be in Vietnam?
Filtration:The "problem" with any outdoor pond is not just the fish waste but everything else that can and will get blown in, leaves general dirt etc.
In the main there are two types of filtration systems. Pump fed or gravity fed.
Gravity fed Gravity fed are usually best because you can make the pond floor slope to a central point and install a bottom drain. Which in turn feeds a vortex chamber. However here in lies the problem. In order for a bottom drain to work well it sucks in water and dirt, in order to do this it needs an opening of around 2cm at least, but as you want cardinal tetras they are small enough to get sucked in and..... you can't put a mesh on the inlet as that will stop the dirt from being sucked in, or if you tried a mesh it, it will soon clog.
Pump fedThat leaves you with the option of pump fed filter, a filter pump has large holes in order to be able to remove any large waste, but will still have the same problem with regard to sucking in small fish.
GravelOr you could go with an under gravel filter, like fish tanks use, there is one available for ponds called the spider filter. But like a fish tank under gravel filter, you will have to empty the pond and clean all the gravel on an as and when basis which is not an easy task (trust me) Also an under gravel filter can not remove large things such as leaves etc.
Plant filtersI have yet to see a "this will work" idea for a pond that involves a balance between fish water and plants, and of course the more plants you have the more waste you create as and when they die (Usually when you are not looking) so you will need external filtration.
Water depthThe water depth of 60cm will be fine if the pond is in Vietnam, it only has to be deeper to stop it from freezing. Which does happen here in the UK.
ConstructionAlthough the depth will only be 2 feet, you would save yourself a lot of future trouble if you build the pond from concrete (Unless its really really huge, lake size) the reason is simple. Being made from concrete it will never move or collapse (if its done right) where as a pond attracts a lot of visitors and the edges may become unstable and give way. It is possible to not use concrete if the pond is big and you have room for gently sloping sides, but it is down to size of the pond.
FinallyWhat ever you choose to do, take pictures as you go and post them here. I wish you good luck.
Good quality costs. Bear this in mind before you start.
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