K1 kaldnes filter design

[dave w]

I'm going to make some filters and have some design questions.  I'll be using the K1 media.  If people aren't familiar with it, it's like a small bioball, like a piece of pasta, a circular wheel, about half an inch diameter, white plastic. The filter is filled with this neutrally bouyant media which, when colonized by bacteria, become slightly negatively bouyant.  At the bottom of the filter, a lot of air bubbles up through holes drilled in PVC pipes and the K1 pieces vigorously knock into each other, sloughing bacteria off the outside of the wheel whereupon it falls to the bottom of the filter.  Thus they are self cleaning.  Most people use a 5 gallon bucket for this filter.  They pump in water from the sump and the outlet goes back to the sump to be recirculated in the tank.

 

My concept is a little different.  My sump is beside the tank and has the same water level so the return pump has no head pressure.  My tank drains detritus from the bottom of the tank which gravity flows to filter.  The bottom of the filter is conical so the fish poop and dead bacteria fall to the bottom and get pumped out.  The filter is 16"-18" deeper than the tank so the detritus has a place to fall down the cone. I hope my wording here is clear enough for people to understand.

 

So here are my design questions.  One-- it seems the PVC pipes and all the air flow should be located around the perimeter of the filter so the media floats up around the sides, and then comes back down in the middle of the filter in a circular rotation.   That should give the sloughed off dead bacteria a place to fall to the bottom of the filter.  Does this sound right in a filter that is about 14" diameter?  

 

Two -- Would it work better to flow ALL the tank water through this filter, not just some of it? Do you think this filter of about 30 gallons would handle the water flow of about 400-500 gallons per hour?  If the water coming off the bottom of the tank enters the filter about 12" above the filter bottom (to give room for the cone to accomplish its purpose) I'm guessing I'll put the PVC air pipes into the K1 media reactor about 6" above the inflowing water, or about 18" from the bottom of the cone.  Sound OK?  The logic for putting the air 6" above the water source is so that the fish poop has time to fall down instead of getting caught up with the upwelling air.

 

Three -- where should I place the submersed pump so it doesn't suck air out of the K1 filter?  I'm thinking that some type of side slats would keep air in the media reactor but let water out to the pump.  

 

I could also have the water leave via the screened top of the K1 reactor and then flow down on the other side of a divider for 24" or so to the pump and maybe put some fine air bubbling in the countercurrent water flow for skimming.  Maybe I'm trying to do too much and it wouldn't be as efficient as a regular skimmer. 

 

How would you improve this design?

Edited February 12, 2015 by dave w

[Mattiejay6]

So I currently use k1 for my clown tanks. Your design ideas are interesting and not sure I can really give advice on their effectiveness.

 

This media is very lite and floats. The biggest thing I discovered was using good flow and not having any dead spots. I have the water coming from the top of my filter tube via maxi 1200 and the water goes through plastic mesh on the bottom to exit. Since the media floats having the water come from the bottom created dead spots where media would group up and not move.

 

Why do you want to add air to it?

 

I love this media

[dave w]

Mattiejay6, I have also heard great things about this media.  I am sure it does a great job for you by flowing water down through it, but hatcheries use air to keep it mixing energetically in a container of water.  The more energetically the k1s bounce into each other, the more dead bacteria is abraded off the media which can be removed from the system.

 

In a regular home aquarium your electric bill might not be noticeable, but in a larger setting the operating rule is that "it is cheap to put air into water but expensive to put water into the air."  

In other words, air is light and you can squeeze it underwater for just a few watts of power.  But water is something like 60 pounds per cubic foot, and lifting that several feet into the air takes a lot of watts.  Either way will work but moving air is easier on the wallet.

 

It sounds like your maxi 1200 is located in your sump and pumps water to the top of your tube and the bottom of the tube exits back in the sump.  Is this correct?  It's like a trickle filter in a pipe instead of the old buckets we used to use filled with bioballs.   I like your application but it is different than my situation.  I don't have water falling from the tank to a sump below and I don't want to pump water into the air.  So I will vigorously bump the media into each other inside a container of water.

[zygote2k]

Why not use biopellets in a large reactor that is fed water from the bottom scavenging system and use a large blower to agitate the pellets? Seal the top to prevent salt creep and the surface water should flow into something else,

[dave w]

I think that's a good suggestion but a friend tried biopellets and they didn't work for him.  He ended up giving the system away to someone else.  But Rob, I think you're pretty smart about filters, so why not try both?   There are a lot of large scale fish people who rave about the kaldness media, I don't know if biopellets have as strong a following.  If biopellets work that well and are a reasonable price, I could probably find a way to make both types of filters.

 

Would a blower agitating the biopellets cause them to prematurely get worn down?

 

In either case I like the energy efficiency because I have a big system.  Bubbling the either media with air instead of pumping water will greatly reduce my electric bills.  Maybe I can set up two systems side by side handling the same bioload and see which has lower nitrates.  Thanks for the idea.  I'm thinking that your suggested "large reactor with a sealed top" might be a couple of 5 gallon buckets.  

[zygote2k]

Biopellets do work- they sometimes take longer times in certain systems to process nitrate.

I use them in heavily fed and heavily stocked tanks. Plus they have the benefit of allowing feather duster and sponge growth.

[dave w]

I have heard mixed reviews on biopellets but all the reviews of K1 media have been great.  Has anyone used K1 and just found it to be average?  

 

Rob, have you used enough K1 to offer a side by side opinion of which gets more filtration done in the same space?

[zygote2k]

never heard of or used K1. There have been numerous bio-media introduced every year that make great claims of performance. K1 looks like smaller versions of the Tetra Pond Filter media that was introduced 20 years ago. 

Why not make a zeovit tumbler? Looks like you can use sintered glass too.

Biopellets are different in that they are actually consumed by bacteria.

 

A big Bio-tower will do the trick just as well- Petsmarts use large towers and seem to be able to keep the nitrates at zero with thousands of fish being passed through the system at any given time. They saturate the water with o2 and are used as a degasser.

Edited February 14, 2015 by zygote2k