Filtering my pond.

[extra_g]

So I have had my pond up and running now for 4 months. Below is the link with some information about my setup.

https://www.gardenpondforum.com/threads/i-just-put-a-pond-in-the-ground-and.23973/

Summer is approaching and I am beginning to get string algae growing more than I would like or expect as well my water is looking a little murky. I have tested the water, nitrite, nitrate, ammonia and phosphates are near on non existent (using API test tube and drop kits), hardness was low but I have adjusted that and the growth has reduced quit a lot but I believe there is still to much string algae growth.
When looking at my filter (several plants in the gravel filled bottom fed overflow to pond, see 2nd photo) and pulling back some of the top gravel to see the water the water has lots of muck in it. the muck is in tiny clumps but when disturbed breaks up and is very fine.
1. Should my filter be like this?
2. Does the bacteria breakdown this matter in my filter or should I filter my water entering the filter? How?
3. Would I be better removing the gravel from the filter and filling it with bio media and plutting the plants into a spill way so the water goes from the pond to the filter to the spill way then return back to the pond?
4. Would keeping what I have and using zeolite help?

 

[Lisak1]

Are there fish in this pond? Are you pre-filtering the water before it gets pumped into the bog filter? Planted filters aren't really meant to provide mechanical filtration so I suspect that may be part of your issue. The gravel will quickly clog up with organic material.

 

[extra_g]

Are there fish in this pond? Are you pre-filtering the water before it gets pumped into the bog filter? Planted filters aren't really meant to provide mechanical filtration so I suspect that may be part of your issue. The gravel will quickly clog up with organic material.

Yes fish in the pond, no filter before the gravel filter. Because I am limited for space I am thinking that perhaps the best solution may be to remove the plants and the gravel from the tub and converting the filter into a top feed filter over some foam pad with the media below that. From the filter to a spill way to the pond. This way the foam can act as my mechanical filter which can be easily removed and cleaned.

 

[Lisak1]

Is the pump submerged? If so, you could try a small profiler on the pump. If you reverse the flow through the gravel and add a filter pad, I think you'll have to be careful to watch it so that it doesn't clog and divert water out of the pond. That's the big downside of a down flow gravel filter.

Small ponds are definitely more challenging in lots of ways!

 

[extra_g]

I emptied the filter yesterday and it was not pretty. There where nice white healthy roots as well as brown rotting roots. The water was murky and a bit smelly which to me told me there was anaerobic bacteria thriving. I am picking up a little wheelie bin today and going to convert that to a biological/mechanical filter.
Now I just have to work out what foam and how many layers. My thought is to place a 1"/25mm coarse foam on top and under that have a 1"/25mm medium foam, so in total 2"/50mm of foam as a mechanical filter and have my media under neath. The area that the media has to fill is approx 400x400x500H in mm. I could beef up the number of foam layers to probably 4"/100mm even more.

 

[extra_g]

So after removing the old filter I have built myself a spillway which is being feed from my mechanical/bio filter. Waiting on delivery of my foam so I can put in my filter box. I am going with 2 or 3 50mm coarse foam layers then a medium layer with some biological media under that.

Since being in action this new system (even without the foam/mechanical filters in) is giving very good results. The algae growth has reduced and the pH is at a better level. I think what ever was happening in my previous filter was increasing the waters pH. After testing the water today everything is great.

In the spillway I have two sections and what I would like to know is if the suns rays will UV filter the thin stream of water as it travels from the upper section to the lower section?

 

[extra_g]

My filter foam arrived a couple of days ago and my filter is now setup. I have had some algae settle on the pads and I cleaned the top one only to find that the algae is travelling through the pads so I have put a stocking over the filter inlet to catch the finer particles and then simply dispose of them. This way they are not building up in my immature filter. The water is clearing slowly and the algae in general has reduced, I am also going to be adding zeolite every week or two until my water is crystal clear.

 

[addy1]

It all takes time. Happy it is clearing up for you

 

[extra_g]

It has been 11 months since my last post and 15 months since my pond was installed and landscaped. The garden has now established and the pond is crystal clear. I ended up buying a product called Splosh after a bit of research online and hey presto the pond cleared up after about 4 weeks maybe 5, you get multiple sachets in a packet of Splosh which you put one in every two weeks. I did one course and never had to reapply and as you can see from pictures the waters is clear.

 

[addy1]

Looking good! Thanks for the update!