Pond Boss Forums INTRO Questions & Observations Researching iron filtration for fish rearing.

Hobbyman,

Not "gravity flowing through the filter," but we are on the same page as far as float controlled flow tied to the well pump. I found an example of the concept with cisterns that collect rainfall but need t be augment with "mains" water if the level gets too low. Even found one website that sells the hardware ready to install. This one apparently uses weigths instead of floats. (Haven't actually investigated it yet.)


Tank/pump wtr lev control



My thoughts were if the epdm pit is sufficently large enough to allow enough retention time, after dropping through a packed column via gravity for aeration, then a pump is used to pump the ferric iron laden water from the pit through a DIY Sand & Gravel filter like the one below. It's good for up to 2000 gph ( gpm). Still in the air on what to do there but if the tank(s) are lw enough the fresh water can enter via gravity and the rest of the flow may be pumped from a sump tank.


S & G filter


The above filter is used in koi ponds to produce gin clear water after some kind of primary filter to remove most of the feces and uneaten feed. Should work great for water that is otherwise clean except for the ferric iron.

The gravity operated packed column I already have set up, and consists of five gallon buckets in a vertical connected chain full of media. I used it to aerate the well water before it went to the trout pond. It has the added benefit of blowng off hydrogen sulfide gas. And the media promotes catalizing the ferric iron from its ferrous bicarbinous state with a coating of hydrogen oxide.

Keep in mind this is all still fluid but my focus at the moment is iron removal.

Here is the solution an Indiana trout producer uses to remove iron. (Mike Searcy Whitewater Trout Farm Cortland, Indiana.) His max well flow btw is 18 gpm to produce 5000 lbs. of trout.

When the water is pumped out of the well it goes through some cheap venturi, into a bulk tank with a float switch that regulates the well pump. I then pump it through 1.5 cf mineral tanks with multimedia. After that it is filtered with 50 micron pleated filters. I back wash the mineral tanks several times a week and change the pleated filters about every 20 days. I have 4 filtration units that can feed 3 branches. That way I can be servicing one system without affecting water flow. I am only filtering water for my nursery and my purge tank. That serves as make up water for my hybrid recirculating system. It may only be 5 gpm or as much as 18 gpm.

Cecil,
Makes sense to me now (takes a while). I like the air lift scour the filter uses. Should be effective in getting the iron out of the filter bed.

I have never seen a float valve with a "dead band" like that - interesting. I can see some potential uses for that valve for dosing situations.
Dale

No worries. I went back and noticed I wasn't very clear.




I found it rather interesting too!

Here is my packed column over the well pit. As you can see it collects a lot of iron hydroxide!




The buckets have a circle cut out in the bottom with a recess left to hold plastic cage netting to keep the media in.

According to my D.O. meter I get 90 percent saturation by the time the water exits the bottom bucket. I have ideas to increase it even more.

My first DIY packed colum was 10 inch PVC pipe. The buckets work better due to more exposure of air between the buckets.

Cecil,
Your thread about iron has beem extremely helpful. We just dug our first 2 acre pond to raise largemouth bass fingerlings. Our well water is coming out with an excessive amount of iron. I am thinking of trying some of the methods mentioned.

When the water goes through the bottom bucket, is it going into the pond, or has to sit in a holding area before you pump it to your pond?

Our well pumps at 320 gallons per minute, so I'm also a little concerned by that.

That's the picture I was looking for!! I am familiar with his system. He pumps 50 gpm and while the water falls to a holding tank, it doesn't stay there very long, overflowing to a pipe that leads to the pond. The holding area is about 3' square and maybe 24" deep.

If I may ask, what diameter is the well casing, what dia pipe is going to the pond, how many hp is the pump and who made the well pump?

I'm really considering doing the same, poking a well down to fill the pond. There is plenty of water here at 100' depth.

Esshup,

Thank you, again! I believe the well casing is 6 or 8 diameter, the pipe to the pond is a 4 inch and 10 hp. Not sure who made the pump.

Is there a way to turn my gpm down I guess? I am new to all of this. Once we saw the iron, we changed the discharge to shoot into the air some, then have the water flow down a riprap ditch to attempt to rid some of the iron. I don't know that it has helped much and that's why I'm looking at a true filteration system.

If the pump has a variable frequency drive, yes it can be turned down. Think of a motor that can run faster or slower. If the pump isn't like that, then choking down the flow puts more strain on the pump (backpressure) and shortens it's life. How short? I can't say.

In simple terms, putting O2 into the water makes the iron precipitate out if the water would go into a pool and not have a fast flow to the pond. Sort of like a settling pool.

The more air (Oxygen) you can get into the well water, the better.