FAQ – Filtration

What type of filtration is best?

There are quite a few options when it comes to pond filters. They are sized according to the size of your pond, the type and amount of fish you are wanting to keep and also the conditions your pond will be in. If you’re needing help in choosing a filter system for your pond you can speak with one of our friendly staff at The Pond Shop or even send us an e-mail. If you can give us the dimensions of your pond and the type of fish you wish to keep we can show you your options.

Furthermore, you can see our article on the types of filtration HERE - https://www.thepondshop.com.au/help-centre/filter-systems/  which gives you more information on the types of systems that are available and things to look out for.

Why isn’t my filter keeping my pond clear?

There could be a number of reasons for this. These include:

• Fish Stock – If you overstock the pond you will need to oversize the filtration to suit. Even if you are starting small you have to remember that the fish will grow so you will need to allow room for growth.
• Feeding – Fish can be described as opportunistic eaters this means they will take any chance they can to get food. Overfeeding can have massive impacts on your fish, filtration and the water quality.
• UV Light – The UV light is the foolproof way of having crystal clear water in your pond. This doesn’t mean you won’t have any algae, it just means your water will be clear and you can see through to the bottom. The UV light does not kill the filamentous algae. The UV light may not work if it is too small a size for the pond system!
• You may have the incorrect size filter for your pond system. Please contact us to get an idea on the size filter you would need for your pond. There are a number of factors that go into the size filter you may need – fish stock, pond size, fish type etc.

Can I use a Skimmer?

Skimmers for ponds are available and are great for catching leaves before they fall to the pond floor. Skimmers can be attached to the inlet of a pump or there are some available that can be built into the side wall of your pond and some that float with their own pump. Skimmers are not really a necessity for a pond but are an option if you are planning on placing a pond under trees. Alternatively (especially for smaller ponds), you can buy a fish net to scoop out any leaves that may fall into the pond.

I have nowhere to put a filter. What can I do?

In most cases, larger pre-filter sponges can be adapted to the front of a pump instead of the smaller caged filter that pumps come with. The next step from here is the All-in-One System. They combine the pump, filter pads, bio balls and UV light in a compact case that can all be fully submerged in the water.

However, if you are planning to have a Koi pond it is recommended to find a place to put an external filter. Koi are the dirtiest fish you can keep and it will only lead to further issues down the track if you don’t plan ahead. If it is an existing pond and you have no space next to the pond you can always go for a pressurised filter. These filters are able to be put away from the pond if needed and you would then just run some tubing to and from the pond.

How long does a UV light last?

UV lights need to be replaced every 12 months as they lose intensity after a while and become ineffective.

How long will my filter pads last?

This varies depending on a number of factors:

• How often you clean them
• What you clean them with
• How many fish are in the pond
• How much debris is in the pond

You should at least be able to get a year or two out of them. Replacements are available.

How do I know if my UV is working?

The most obvious sign that the UV isn’t working is how your pond looks. If your water is clear and you can see through the water then the UV has done its job. This doesn’t mean you shouldn’t have any traces of algae. The UV only targets the murky green water, it does not get rid of the filamentous algae. So therefore, if your pond is murky brown or green your UV unit is not working.

In most cases, the UVC will have a small window that allows the illumination of the UV to shine through just enough to indicate it is on. The easiest time to check if the UV is working is at night when you should be able to see the UV light glowing through the window on the unit. If the UVC is older and the window is dirty, or you still cannot see any glow from the UV then you can check it by removing the unit from the filter and testing it manually. Two things to note here. 1. The light will not turn on just like this as it has a safety switch. When the lamp holder is in place on the filter the safety switch is pressed in which turns on the light. So in order to see if the light is working with the lamp holder removed from the filter you will need something to press down the safety switch. 2. DO NOT LOOK DIRECTLY AT THE LIGHT! This is very important! It can damage your eyes. It’s best to have it behind or under something that will still allow you to see the illumination without looking straight into the light.

If your light is working and your pond is still a murky green there could be 2 reasons for this. 1. You haven’t replaced your UV tube for a long time. UV tubes need to be replaced every 12 months as they lose intensity after a while. 2. Your UV system is too small for the size of your pond.

If you are uncertain as to whether the unit is working we are happy to take a look at it if you bring it in to the shop.

Can I make my own filter?

Certainly! We have all the materials needed to make your own gravity filter. Just keep in mind you want a container that is UV resistant so it will last. We sell bio balls, fittings and Filter Foam Sheets in-store.  Before going ahead and constructing your own filter you may want to consider the overall cost and cleaning that may be involved.