Biological filter question

[cas]

I have an Aquascape biofalls biological filter. It has always worked well for me, but I was wondering:

1. Do the nitrifying bacteria in the biological filter need light or do they need to be kept out of the sunlight?

2. Do plants on top of the biological filter help or hurt (by trapping sediment)?

3. Are the nitrifying bacteria getting enough oxygen from the water that is pumped into the bottom and flows upwards through the media, or do they need more oxygen?

4. The bio-falls is not cleaned during the season; it is only cleaned out in the fall. Since it is not backwashed for cleaning, what would be the best media to use in the biological filter?

 

[Meyer Jordan]

1. Do the nitrifying bacteria in the biological filter need light or do they need to be kept out of the sunlight?

Nitrifying bacteria are photo-neutral.

2. Do plants on top of the biological filter help or hurt (by trapping sediment)?

Neither.

3. Are the nitrifying bacteria getting enough oxygen from the water that is pumped into the bottom and flows upwards through the media, or do they need more oxygen?

This will depend on several factors not directly related to the biofalls filter. What is the fish load in the pond or more correctly what is the BOD (Biological Oxygen demand)? What is the surface area to depth ratio? What is the ratio of aquatic plants to fish? Usually if the fish are not exhibiting symptoms of low Oxygen the sufficient Oxygen is in the water to sustain all bacterial growth.

4. The bio-falls is not cleaned during the season; it is only cleaned out in the fall. Since it is not backwashed for cleaning, what would be the best media to use in the biological filter?

Under the conditions stated in the question, media with larger void spaces, such as Lava Rock, would be the better choice

 

[cas]

Thanks @Meyer Jordan . I have been reading conflicting information and wanted to verify that I didn't need to change anything next year.

 

[Meyer Jordan]

Thanks @Meyer Jordan . I have been reading conflicting information and wanted to verify that I didn't need to change anything next year.

I would add that the 'clean once a year' statement from Aquascape should be taken with a grain of salt. Like most other aspects of any pond, it depends on the individual pond. Cleaning frequency of any type of filter will depend entirely on the amount of TSS (Total Suspended Solids) generated by the pond. This will eventually clog first, the filter pads, and then the filter media. This is especially a problem if no skimmer module is in use. When the filter pads become clogged the water flow is 'channeled' around the perimeter of the filter mats effectively bypassing much of the filter media thus reducing the efficiency of the biofilter as a whole. In ponds with a heavy fish load and/or lots of plants, I would recommend that the filter mats be cleaned at least twice a year or even more frequently. This should be determined by the pond owner.

 

[cas]

Thanks. I will analyze the bio filter when I dismantle it and clean it this month. I do have a skimmer with a filter mat and net that I clean daily in the summer. Previous years it seemed that the water was still able to flow through the media in the bio falls, but I will double check that this year. I had quite a lot of string algae on top of the bio falls this year, so maybe the water flow was restricted. I left the string algae in the bio falls because I felt it was keeping the suspended algae in check and there was no string algae in the pond.

 

[Meyer Jordan]

'Channeling' is fairly easy to spot. Isolated areas of increased bubbling or turbulence on the surface of the water in the biofalls is indicative of 'channeling'. It is usually seen around the inside perimeter of the biofalls.

 

[cas]

OK. So I just went outside to check. The string algae was removed last month so the top of the bio falls is totally open. I can not see any water movement in any specific area (except over the falls ). I looked around the perimeter - didn't notice any increased water movement. In fact, the top of the water is like glass, so I have no idea where the water is coming up from. Good thing or bad?

 

[Mucky_Waters]

Thanks @Meyer Jordan . I have been reading conflicting information and wanted to verify that I didn't need to change anything next year.

As usual Meyers suggestions seemed very practical and logical, but on a side note, I find it very disconcerting that you were able to find conflicting information about aspects of this hobby floating around out there. I'd hate to see the complete unity we have now disrupted by one or two radical free thinkers dispersing their conflicting ideas. Mark my words, if we don't act quickly to snuff this stuff out now then next thing you know we will start seeing lengthy arguments and debates among members of this forum going on here about clearly established things like whether to put rocks on the bottom of ponds? or what is the best method for getting rid of green water algae? or whether or not bacteria in a bottle products actually help or not? Once we begin questioning those basic things chaos will ensue.

 

[Meyer Jordan]

OK. So I just went outside to check. The string algae was removed last month so the top of the bio falls is totally open. I can not see any water movement in any specific area (except over the falls ). I looked around the perimeter - didn't notice any increased water movement. In fact, the top of the water is like glass, so I have no idea where the water is coming up from. Good thing or bad?

And that is how it should be.

 

[cas]

And that is how it should be.

Yippee! Thanks.

 

[cas]

I'd hate to see the complete unity we have now disrupted by one or two radical free thinkers dispersing their conflicting ideas

I agree. It is so hard to determine what is fact and what is opinion. Very thankful for the knowledgeable people on this forum that take the time to answer questions.

 

[Dave 54]

OK. So I just went outside to check. The string algae was removed last month so the top of the bio falls is totally open. I can not see any water movement in any specific area (except over the falls ). I looked around the perimeter - didn't notice any increased water movement. In fact, the top of the water is like glass, so I have no idea where the water is coming up from. Good thing or bad?

@cas All our filters have lids to them and thus all filter and bacteria are in the dark and as such are as @Meyer Jordan suggests "photo-neutral",
if thats any help to you at all
But I'm rather a tad confused with your filter media I'm afraid ?
When you say aqascope bioballs dont you mean Aquaone bio balls or Aquapond bioballs as I've never come across aquascope bioballs before but use the Aquaone/pond bioballs along with K1m filter media and Bio chips .

Dave

 

[Meyer Jordan]

To clarify, photo neutral means that cell metabolism is not influenced by light or dark. Filter lid or no filter lid...it doesn't matter.

 

[cas]

But I'm rather a tad confused with your filter media I'm afraid ?

Hi Dave. I never stated what filter media I am using. This year I used pieces of filters.

 

[Dave 54]

Hi Dave. I never stated what filter media I am using. This year I used pieces of filters.

Sorry @cas miss-read biofalls for bio balls however I would like to know exactly what media you have in your filter just out of interest

Dave