To clean or not to clean my bio balls! That is the question.

[ShawnC]

I've just read that you should clean your biofiltration out but I'm a little confused about this. I was under the impression that if my mechanical filter is doing its job, I shouldn't touch my biofilter. Isn't the stuff thats growing on the balls the "beneficial bacteria". Doesn't taking them out and washing them off kill the "beneficial bacteria"? If i should do this then how often?

I have a DIY sieve (mechanical filter) which filters out everything above 160 Micron. This water ends up at the bottom of a 55g plasic barrel via a 3" PVC pipe and rises up through the media. Then it spills out another 3" PVC pipe and run through a UV light and back to the pond it goes.

Thoughts?

 

[sissy]

sure is and if you clean them you will loose it .I just do a light flush on my lava rock to get some of the gunk to go to the bottom flush out .I have to use a small pump to get the gunk out I got tired of scrapping my knuckles .I would be like the bad I clean my pond and power wash it person .

 

[JohnHuff]

Don't clean your bioballs. But as I understand it, all the n-bacterias die during winter and come back again when the temp. is warmer, so they'll come back.

 

[Catfishnut]

I have been studying these filter systems intensively for a few years. The impression that I have gained is that if you sediment and prefilter system is working superbly, there should be no reason to clean or purge the bio-converter tank. Just leave it alone unless your sediment filter is not doing the job.

I am just learning some of the ropes here, so my opinion is just what I have developed with the bits and pieces that I have gained along the way and my opinions are not really refined and polished, but they are based upon good facts and information. Therefore, I say that as long as the mechanical filter is doing its job to screen out ALL the solids, the bio-converter should never require cleaning. The bio-converter should only have the media, the bacteria and the "solids free" water flowing though it. This would be the ideal scenario and what I am striving for, but this isn't a perfect world, so your bio-tank will eventually require some limited cleaning. I wouldn't clean it aggressively, maybe just a light rinse to wash out the spent bacteria and any fines that may have passed through the prefilter. I read often that you should use your pond water for this purpose and avoid using any chlorinated city supplied water source.

If you shut your pond down through winter, I don't think any of this matters much as the bacteria will die off at temps below 35°F anyway. The bacteria are naturally occuring organisms, so they will come back in the spring when the water warms up and the bio load starts to redevelope. In other words, if you are going to clean your media and tank, do it in the middle of winter when everything is inactive, dead or dormant.

Catfishnut

 

[sissy]

I am not sure how cold it gets in Texas .I know mine is still running and has all winter and it is clean and plants are starting to grow .I did not flush my filters all last summer because of all the plants floating in the filters and the grasses colleen told me about really do clean the water real well .I have them all over my pond now and just pull them to trim the roots because the roots will take over if you don't .Then you may be trying to lift a 100 pound clump out .i am going to divide them soon

 

[crsublette]

1) I've just read that you should clean your biofiltration out but I'm a little confused about this. 2) I was under the impression that if my mechanical filter is doing its job, I shouldn't touch my biofilter. 3) Isn't the stuff thats growing on the balls the "beneficial bacteria". Doesn't taking them out and washing them off kill the "beneficial bacteria"? If i should do this then how often?

4) I have a DIY sieve (mechanical filter) which filters out everything above 160 Micron. This water ends up at the bottom of a 55g plasic barrel via a 3" PVC pipe and rises up through the media. Then it spills out another 3" PVC pipe and run through a UV light and back to the pond it goes.

Thoughts?

1) Depends on your system. If the mechanical aspect of your filtration system is failing, then you will need to backflush the bio-filtration to drain the settled debris. If your bio-filtration is quite small with little surface area, then, eventually, the heterotroph bacteria population will grow so big that it will start to consume, as their food, the autotroph bacteria. Autotroph bacteria are the main actors in the nitrification cycle, that is ammonia > nitrite > nitrate. If your bio-filtration system is quite efficient and is bigger allowing more surface area, then there is plenty of room for the heterotrophs to do their thing and your autotrophs to do their thing. Supposely, over a decade or few, then you might have to clean the bio-media if your bio-filtration is quite efficient with more surface area.

I wouldn't get ahead of your self assuming you need to clean the bio-balls because someone told you to do it "just because".

Ultimately, a good way to know if your bio-filtration is failing you is by testing the Total Ammonia and Nitrite levels in the pond. During the summer season, if these levels increase above 0 and stay their longer than 24 hours, then your bio-filtration unit is failing. It might be failing due to gunk and debris accumulating in the unit and on the bio-medium, slow water flow through the unit, not enough material in the unit, unit is too small, or unit is not built well.


2) Not all mechanical filters are created equal in performance of seperating solids and debris prior to the water entering the bio-filter.


3) Yes, and refer to my #1 answer.


4) 160 micron might sounds small to you, but this is just small enough to capture the large debris. To capture the smaller floating debris, then there are the polishing mechanical filters that go below 100 microns all the way down to 40 and sometimes even lower depending on the filter. Polishing mechanical filters are filters such as bead filters, the sand & gravel upflow filters, or a pressurized unit called the Multi-Cyclone 50. A very fancy mechanical filter is a Rotary Drum Filter that is an all-in-one large debris and polishing mechanical filter in one package.

The small floating debris, below 160 microns, will eventually settle on your bio-media (if it is not fluidized) and on the bottom of your bio-filter. Over time, this will reduce your bio-filters performance.

 

[mariobrothersleeve]

I clean mine frequently(during summer months) with disguarded pond water, it usually has alot of gunk in it. Its a good habit to clean with the amount of bad bacteria that grows after time. I am unsure of how cold it get there, but up here i just got to mine last week due to weather, from last october. I am into salt water, and they are a big issue for nitrates and phosphates. A clean filtration equals a clean pond. Good luck

 

[Waterbug]

Dead algae cells are about 5 microns. 160 microns may seem small but a lot of waste is smaller. A mechanical filter doing its job doesn't mean it creates pure water.

The bacteria we care about in bio filters look like:

The black dots are bacteria, the light gray is the biofilm the bacteria creates to live on, the arrow shows the flow of water thru the biofilm channels and the dark gray base is what the biofilm attaches to, like the bio balls.

A single 5 micron bit of decomposed algae cell can fill a biofilm channel. A layer no thicker than the dust on your TV can cover the boifilm completely. That reduces water flow thru the biofilm channels so the bacteria have less access to ammonia, nitrite, O2 and carbon.

Also, waste filled channels allows other kinds of bacteria (bad type) to move in to consume that waste and push out or kill the good bacteria.

This is how bio filters that wash the biofilm 24/7, like Trickle Towers, Bakki Shower and Moving Bed, all out perform static submerged media by 30 times or more. They greatly increase bacteria access to food and reduce the ability of bad bacteria to kill the good.

Whether or not bio balls need to be cleaned is more of a question of what you need the filter to do. If for example you're measuring ammonia or nitrite then cleaning the media could get the bacteria going again. However, you might have to clean the media daily or weekly depending on the amount of suspended waste your pond has and how water is flowing over the media.

If you're not measuring ammonia or nitrite then there's no reason to clean the media because it's working good enough, and/or nitrifying bacteria has set up shop other places like inside your pump, inside pipes, etc., where it can stay clean. IMO this is the case in virtually all ponds using a static submerged media filter. That if the filter was removed completely the keeper wouldn't see any increase in ammonia or nitrite. Keepers install a filter, measure no ammonia, and give 100% credit to the filter (and of course themselves). But that's just a lack of understanding the bacteria.

There's been a long time myth that water can't be moved through bio filters too fast. Often called "dwell time". Very silly myth. If you increase the amount of water going through your filter it will reduce the amount of waste settling on the media and it will need less cleaning. Increase the flow enough so the balls actually move and you'd have a moving bed filter. Bio balls aren't good for moving bed, however they're good in Trickle Tower and Shower filters. So if you can raise the media up out of the water so water flows over the media you should get a much higher ammonia/nitrite conversion rate (like 30x) and you'd never have to clean the media assuming it's kept in the dark.

The issue with pulling bio media out of a filter and washing it, beyond being a pain, is damage to the existing biofilm. In static submerged media the towers of boifilm can grow very long. When sudden moved around and washed the boifilm can break up and be washed away. In a moving environment like Trickle Tower, Shower, Moving Bed, the biofilm has to grow where it can and to the limits of that environment. So you might get a lot more shorter biofilm, or thicker, instead of fewer but longer thinner biofilm.