Treat Water Before New Filter?

[Paffman]

Maybe a stupid question, I have just bought a pond filter (Blagdon Clean Pond Machine) but my pond is green. Should I treat it with Pond Clear before I fit the filter or just let the filter do it's job?

Steve

 

[mrsclem]

Do you have fish in your pond? If so, using any chemicals other than a dechlorinator could possible kill fish. Many people have come to this site saying they used algaecides, etc and their fish died. Let the filter do its thing.

 

[Paffman]

We have not got any fish yet, that's something we will do when we get the filter and water condition sorted. The Blagdon Clear pond says it is fish safe. OK will install the filter and let it do it's job. Thanks for your reply.

 

[brokensword]

a filter is not going to solve your green water issue; algae is too fine to be caught that way. You need lots and lots of plants to outcompete the algae, PLUS, a good sized biofilter. A bog is what many of us use as there's a lot of surface area for the nitrogen cycle. It'll also work wonders when you do get fish.

If you don't have fish, I'd wonder at how much organics you have that are decaying enough to give you such green water. Algae on submerged surfaces is what you want, but the free floating kind feeds off DOCs.

 

[Paffman]

a filter is not going to solve your green water issue; algae is too fine to be caught that way. You need lots and lots of plants to outcompete the algae, PLUS, a good sized biofilter. A bog is what many of us use as there's a lot of surface area for the nitrogen cycle. It'll also work wonders when you do get fish.

If you don't have fish, I'd wonder at how much organics you have that are decaying enough to give you such green water. Algae on submerged surfaces is what you want, but the free floating kind feeds off DOCs.

We did a part water change and de-sludge a couple of weeks ago, bought new plants, grasses and oxygenation plants, but the water went green, so no dead matter to biodegrade. Having said that the filter we have now is on it's last legs, UV broken etc, hence the new Blagdon Clean Pond Machine 10000 with UV. Our pond is only 8ft x 5ft and 2.5ft deep in places.

 

[poconojoe]

Yep, one of the most common threads start with someone posting they added such and such "fish safe" additive and all their fish died.

You don't have fish yet, so that, at the moment, is not a concern.

But, instead of masking the problem with chemicals, it's best to find the root of the problem.

Green water, as others have stated, is caused by the presence of free floating algae.
That algae is nature's way of attempting to balance the properties of the water. The algae feeds on the excess nutrients in the water. The bulk of abundance of nutrients usually comes from fish waste, but you don't have fish, so there are other culprits at hand.
Accumulated decaying debris on your pond's bottom can be a cause and sun can contribute a bit too.

By using chemicals or a UV light, you are killing all the algae, not just the "bad" algae, but the good stuff too. Plus, the dead algae becomes more food for more algae to feed on. A vicious cycle.

What you need is lots and lots of plants to compete with the algae for food. A fine grade filter can also help catch those tiny algae.
You can line a milk crate or a bucket with holes in it with quilt batting. Have your return water flow into the batting. It will sift out those fine particles. You will have to pull it out and either rinse the batting or change it as needed.

Agree with what was said about bog filters.
I had solid green water before adding on a bog filter last year. The combination of adding the bog and tons of plants in the pond and bog cleared my water. It has never been this clear. It looks like you could drink it. I saw fish I didn't even know I had!

 

[j.w]

@Paffman