Additional filter

[Spartamets]

Hi, I have a 4800 GPH pump that is located in a skimmer box. It heads up to two waterfalls. The main one has my biofilter in the sense that it has a couple of bags of lava rocks and water hyacinths in it. At the bottom of that waterfall is a stream of about 15 feet in which I've put some plants. More plants will follow, but I've been positively swamped at work for the last 5 weeks so haven't gotten to that yet. I'm concerned I don't have enough filtration. While I think the stream is helpful, my concern is that the whole water cycle begins with and is comprised entirely of water that passes through the skimmer. There is nothing for the bottom of the pond.

Recurrent algae blooms--some of which came from overfeeding, which I've since corrected--has led met to think I might need more filtration. I am especially concerned that stuff that doesn't make it to the skimmer essentially doesn't get filtered. Should I add another pump to the bottom of the pond, leading to a small biofilter, or is this unnecessary? This is still my first "season" of ponding (I won't count the winter), so I don't really know what I should just roll with and what I should work to correct.

In other news, we got a couple of (loud) frogs, unrelated to the vanishing tadpoles I once wasted money on, and I officially hate herons, pretty though they might be. My fish are still freaked out, and I still don't know for sure all the fish it ate, although at least one of the ones I know it did eat had a name.

 

[Meyer Jordan]

Additional biofiltration is never a bad thing, but if you are of the belief that it will correct algae issues, you are mistaken. In fact, the end-product of biofiltration, Nitrate, is one of the major nutrients (the other being Phosphorus) needed to support any plant or algae growth. What needs to be done is to reduce (or eliminate) the source(s) of Ammonia that the biofilters are converting and reduce the Phosphorus level if needed. The most common sources are fish poop, uneaten fish food, too many fish and other organic matter like leaf litter.
You could add a bottom drain, but that will only help with the aesthetics because the nutrients will still remain in the pond.
Everyone has heard the slogan "What happens in Vegas, stays in Vegas", well what goes into a pond, pretty much stays in the pond.

 

[CometKeith]

I don't know enough about your pond setup but if the waterfall is not providing enough "mixing" of the water it might be helpful to have another pump. I would suggest one that is set lower but not all the way at the bottom and have it feed your waterfall. I wouldn't bother adding a seperate biofilter as over time if the pond water mixes it will all get filtered. It's interesting that pond water at the top and middle/bottom of a pond can be quite different. Typically the top layer of the water is a lot more oxygenated and it makes sense to mix it if for no other reason to reduce of some of the cold deeper less oxygenated water in your pond with some of the top layer . Everyone's pond is different so it makes sense to experiment and see what works best for your own pond. Obviously if your top layer water is too hot or too cold the deeper water provides a good balance so there are a lot of factors that can come into play beside just filtration. I have always found that added biofiltration helps reduce algae especially if it has a UV light and this in combination with plants in the pond seems to do the trick. I don't know if I totally agree with comments from the poster above about filtration not helping reduce algae. I hope this helps!

 

[Faebinder]

IMO regardless of the volume of the pond and the number of fish, the filtration is inadequate. If you don't wanna mess up the setup you can simply add an external pressurized filter. Lava rocks pores get filled over time.

 

[Spartamets]

Thank you for these helpful replies. It wouldn't be too difficult to add another pump to the bottom(ish) of the pond, run the tubing through a little external filter, maybe with a UV light, and then have that water get added to the main waterfall. I'm pretty sure I could do it without marring the aesthetics of my setup at all, and the extra flow will even help the falls in that regard.

This would not impact my pre-existing plan to add more plants. I started behind the 8-ball a bit; when Spring started I had fish but few plants, because everywhere was sold out of most options in the Fall by the time I was ready to add them. Plants made a huge difference for a while, but then fish started growing. Rapidly. I haven't yet finished putting in the amount of plants that I think the pond needs, so hopefully they will help, too, once they're in.

I had already been thinking about swapping out the lava rocks for more effective biofiltration media, so that advice is well taken. However, I am not sure how to proceed given that they are already populated with helpful bacteria. Should I just suck it up, swap them out, and kind of start fresh with the beneficial bacteria that had been in the waterfall on those lava rocks? If so, this is something I could do to tide me over until I add the extra pump/filter system. I'm not sure when I'll get a chance to add everything, but it won't be right away for sure.

A nice bonus of this is that it will make it easier to persuade myself that I can get more fish (but don't tell my wife that part). Thank you again, folks. Very helpful, as always.

 

[Meyer Jordan]

I don't know enough about your pond setup but if the waterfall is not providing enough "mixing" of the water it might be helpful to have another pump. I would suggest one that is set lower but not all the way at the bottom and have it feed your waterfall. I wouldn't bother adding a seperate biofilter as over time if the pond water mixes it will all get filtered. It's interesting that pond water at the top and middle/bottom of a pond can be quite different. Typically the top layer of the water is a lot more oxygenated and it makes sense to mix it if for no other reason to reduce of some of the cold deeper less oxygenated water in your pond with some of the top layer . Everyone's pond is different so it makes sense to experiment and see what works best for your own pond. Obviously if your top layer water is too hot or too cold the deeper water provides a good balance so there are a lot of factors that can come into play beside just filtration. I have always found that added biofiltration helps reduce algae especially if it has a UV light and this in combination with plants in the pond seems to do the trick. I don't know if I totally agree with comments from the poster above about filtration not helping reduce algae. I hope this helps!

Mechanical filtration will help, plants will help and a UV will provide a band-aid, but biofiltration will not reduce algae growth. If you believe otherwise then you do not understand the Nitrogen cycle.

 

[DutchMuch]

Bio filtration creates nitrates, Plants eat nitrates.
If you want to lower nitrates:
plants
water changes
are your 2 main choices.

 

[Magzire]

What you guys think of alfagrog? Using 15 kg of the stuff in a submerged container I made. If I was to change it, what would you's recommend?

 

[CometKeith]

Mechanical filtration will help, plants will help and a UV will provide a band-aid, but biofiltration will not reduce algae growth. If you believe otherwise then you do not understand the Nitrogen cycle.

Every year when my pond cycles the algae goes away immediately. I'm sorry. You seem like a nice person but I don't understand what you are saying at all and it makes no sense to me. That's the whole point of cycling a pond is that once the bb gets going it removes the food source for algae and it goes away. Of course you need plants to take care of the nitates but it is pretty easily accomplished. The only thing I can think of is you are referring to a pretty sterile Koi pond. Any type of water garden would easily achieve this.
Spartamets. whatever you do don't change your biofiltration media. This will be like starting over and can spell disaster. If you want to change it I recommend to wait until next year. The way you cold do it is run two biofilters side by side. After maybe 3-4 weeks the new media would have enough bb that you could switch it. BB needs running water to stay alive so you would need to switch it in a few minutes and don't use any chlorinated water to clean anything because it will kill the bb.

 

[MitchM]

What you guys think of alfagrog? Using 15 kg of the stuff in a submerged container I made. If I was to change it, what would you's recommend?

This sounds like an expanded clay material that will eventually clog over time, similar to lava rock.

 

[Spartamets]

I don't want to replace the existing biofalls with the new external biofilter, whenever I get it. Instead, I want to add the new biofilter as a supplement, with its water being added to the existing biofalls setup.

I had been thinking about switching out the media in the falls in the meantime, but now I won't. Thanks for that tip; I worried it might risk some kind of serious consequence. I'm glad I asked first (unlike during my build, when I "learned" from my mistakes instead). The skimmer does most of the mechanical filtration, but those bags of lava rocks do a lot, too, from the looks of them. Is there a way I can clean them off effectively without removing the beneficial bacteria?

Once I've got the new side set-up going, I assume I'll then be able to swap out the lava rocks safely. But the question will still remain of how to clean the new media of, um, "mechanical" debris without also removing the bacteria. Nothing is straightforward with ponding, is it.

 

[sissy]

I put my lava rock in dollar store laundry bags and take them out and dunk them in a bucket of water swish them around and then use that water in my gardens .I also use a small dirty water pump in the bottom of my filter to hose off and pump the dirty water out of the filter .I do turn my pond pump off while I am doing this .I have 2 filters one at each end of my pond .I am a very untraditional pond builder

 

[Faebinder]

I don't believe the lava rocks significantly impact the filtration after a while, you are better off with some of the plastic biofiltration options out there as the pores won't get clogged.

The purpose of these rocks or any filtration is to provide surface area for bacteria to grow on to convert ammonia to nitrites and later nitrates.

The problem is that food has phosphates and nitrogen in the form of dissolved organics. Fish eat it and it turns to ammonia and phosphate that algae uses. Plants also use it to grow. It's a closed system and the only way to remove these nitrogen and phosphates circulating is to a- grow plants and cut them so they can grow more or b- grow algae and remove algae or c- constant water changes.

Clearly option a is what you want and occasionally option b or c.

 

[DutchMuch]

I don't believe the lava rocks significantly impact the filtration after a while

lava rock is one of the best growing medias for beneficial bacteria, making it one of the leading filtration methods.. But for example Bio Balls are even better.
Water changes should be done 25 percent a week (very uncommon ik) imo, and in my experience it works with, everything. does not kill off bacteria, rids water of "junk and gunk" and if you have proper matching water to pour or redirect back into your pond, increases the fishes happiness (temporarily), clears water, gets rid of unwanted algae, many other factors to take in and that's just a tiny amount of them.

 

[Spartamets]

I put my lava rock in dollar store laundry bags and take them out and dunk them in a bucket of water swish them around and then use that water in my gardens .I also use a small dirty water pump in the bottom of my filter to hose off and pump the dirty water out of the filter .I do turn my pond pump off while I am doing this .I have 2 filters one at each end of my pond .I am a very untraditional pond builder

That bucket of water swish treatment is a great idea. Thanks, sissy.