Pond Boss Forums Thread Like Summary - Researching iron filtration for fish rearing.

Been immersing myself in everything I can find on the Internet on removing iron from well water (or borehole water as some call it).

This is in regards to a new aspect of my fish rearing business of hatching trout eggs vs. purchasing juveniles from a trout hatchery. And eventually I hope to rear trout in a partial recirculating aquaculture system (RAS).

The concept is quite simple as in oxidizing the ferrous iron bicarbonate to cause it to precpitate into a solid -- ferric iron -- and then filtering the ferric iron particles out. You can do that with aeration, chemicals, ozone, or special media that quickly oxidizes the iron on contact. Examples are greensand, Birm, or manganese dioxide. Many times the filtration material is a mixture of the special media and plain sand. Plain sand, and sand and various grades of sand, course sand, and gravel will trap iron particles in a vessel if the incoming water is sufficiently aerated and for a minimum time of about 20 minutes. Then it's a matter of backwashing or agitating with air and then backwashing to remove the iron particles once they clog the filter up.

The problem with the iron particles are they can suffocate the eggs and fry by collecting on them.

Anyway I was able to develop a simple DIY iron filter in the past to produce a few hundred gallons of iron free make up water per day, for my small warmwater ras's, but producing a continuous 24/7 flow is going to be more of a challenge.

i came to a shocking conclusion on the commercial iron filters out there: You can buy the components and media separately and safe a ton of money! The mark up on those things is extremely high!

I was floored to find prices ranged from over a grand to to over three grand for turn key mineralization tanks, the media, backwash valves and bypass valves for the flow rates I need. Bought separately you can put together a system for as low as 20 percent of that!

I was relieved to see if I went the mineral tank route I didn't have to spend an arm and a leg!

Anybody else mess with iron filtration? Thought I'd share this for those that are rearing fish in tanks or thinking of it, and have iron issues in their well water.

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.