Carbon before chaeto reactor strips Iron and others?
 

I have a carbon reactor (BRS mini) right before my Chaeto Reactor. I'm pushing about 300-400gph through it. I used to have some lower grade marineland activated carbon, and my chaeto was stable and growing a little bit. A few months ago, I changed it out for BRS ROX. I don't know if it's related, but my chaeto pretty much melted away. I do have more phosphates now than I did when it was growing.

There's plenty of phosphates, and some algae in my display tank, but my chaeto is pretty much melted away.

I'm wondering if my carbon is the reason why my chaeto died. Does it just not get any nutrients?

I've started dosing iron, but I wonder if that will help, especially with that carbon reactor.

Careful with dosing iron and don't dose anything that you arn't testing for.

Not the question.

The carbon might be capable of starving the Chaetomorpha. I would have thought otherwise, though. Carbon might have a fairly limited lifetime in our tanks, although there are multiple options on this topic. If you want to try removing the reactor or reducing the amount of carbon in it, that might might help the Chaetomorpha. I'm more skeptical about the iron helping, although it might.

Thanks. yeah I just thought maybe it would be a clear nono for me to run carbon right before chaeto. Literally no water gets to the chaeto without passing through the BRS ROX. It seemed like a coincidence that the chaeto started to melt some time after switching to the ROX.

Does the carbon reactor feed the chaeto reator? Or do you just have the carbon reactor in a sump ahead of a fuge?

Reef octopus VarioS-2 pump in the sump -> BRS Mini reactor with BRS ROX -> Aquamaxx XL chaeto reactor -> chiller -> Sump

All inline being fed by the varios pump.

What is your N03 level? Low levels is usually where chaeto struggles.

Chaeto's uptake of N03 to P04 is 100-1, so it's easy to create a limited nitrate situation.

I find it hard to believe carbon is sucking up all the organics the chaeto uses. It could be creating clearer water than previously and maybe light inhibition is an issue, but that's probably a reach.

I don't recall ever reading about this particular situation nor does it seem that GAC would strip out inorganic nutrients that algae require for growth. The switch to a different brand of GAC seems like a coincidence.

Running 300-400 gallons per hour through a small amount of GAC might not be allowing enough time for impurities to be in contact with GAC and to be completely removed. For your set up, it seems you cannot be stripping your water to an ultra high purity. Still looks like a coincidence.

Other aquarists have reported their Chaeto dying (melting away) mysteriously. Without more information, we cannot eliminate the possibility that your Chaeto was dying before the GAC brand switch.

As for dosing iron, that can help algae (good and bad) growth in some situations but you are pretty much on your own on how much to dose and how often. An article in Advanced Aquarist summarizes the information on this subject.

But actually it is, without testing everything is a guess.

I would say it was nothing more than coincidence as well. Unless maybe your levels were already borderline too low to support growth to start with, and the carbon stripped the remaining out. What are your N+P measuring?

I find it interesting you assume he isn't testing. And if he is or isn't actually wasn't the question he asked, no matter how hard you try to make it. When the order of events was Cheato growing, rox added, cheato dying, iron dosed to encourage growth, focusing on the iron instead of his question doesn't accomplish much.

Are you testing for iron? If so, what is the level?

My nitrates are undetectable on my tests normally. After reading more, this could be the biggest reason why chaeto isn't growing. It's too bad the film algae I have is still growing well and chaeto isn't.

Yup, I read the Advanced Aquarist article, which is why I started thinking about iron. I agree, probably a huge coincidence. Thanks for the input!

Nitrates are undetectable usually (or very very low)
Phosphates are pretty low, about 10 - 20ppb.

I always chalk it up to, someone hears or knows one thing and tries hard to steer a conversation there to trap it into that hypothesis. It usually derails a conversation.

Just so we can get back on topic. YES I test for Iron, like every other thing I dose or don't dose. I have probably every single test you can think of, and multiple copies and brands of each. I've also brought in my water to LFS to test on their tests. i have not, however, used something like an ICP test.

If you know about iron, or have read the advanced aquarist article, or know how iron levels work in a tank, it's almost impossible to test for iron. Iron is used up pretty quickly in a tank. When I tested it, it was undetectable. When I dosed and tested, I saw a blip. But then it was gone again.

Yes, you can dose iron into a bucket of RO/DI and test for it, and it will show. But the organisms use up the iron in a tank pretty quickly.

ICP tests almost always show 0 iron. If you look at threads about it, even on clay-boa with Randy Holmes, you'll see that it's not a good way to tell how deficient in iron your tank is. This is only if I'm completely mistaken, and my iron is being sucked into a black hole everytime I dose.

What film algae is this? Not what grows on the glass I hope?

It's just the usual green film algae on rocks and glass that I've always had. Are there other kinds of film algae?

I don't have any other nuisance algae at the moment (knock on wood).

I think that film you have to scrape off is unavoidable no matter what is running on a tank.

Some people manage to reduce growth on tank walls to very low rates, but I agree that most people will need to clean the glass from time to time. A few herbivorous snails can help, but most recommendations or guidelines lead to overstocking, which causes the snails to starve to death over some number of months.

Why not just put swap the piping and put the cheato reactor first and see what happens?

Personally I would put the natural filtration before any mechanical/chemical filtration since you dont know what all the carbon is pulling out the cheato may need.

Also, if youre not testing for iron dont dose it. Thats just asking for trouble and you have no idea if that is even an issue.

Have you ever tried testing for iron? Check a few posts back about iron testing.

Yeah I might be trying to grow chaeto when the film algae wouldn't be affected by it anyway. Good point. Thanks all.

Also, I guess I shouldn't be surprised when there's the "TEST EVERYTHING BEFORE DOSING" police. :headwallblue:

Iron seems to be consumed very rapidly in our systems, and is present in very tiny amounts in ocean water:

http://www.advancedaquarist.com/2002/8/chemistry

I wouldn't worry about overdosing iron very much, and there's no practical way for hobbyists to test for natural levels.

Not sure if you covered this, but do you test for iron? [emoji14]

LOL!:rollface:

Then yes in your case that type of carbon is starving the chaeto of nutrients due to it being before the chaeto. Its possible the carbon is cleaning the water just enough to effect the chaeto growth. Just switch the 2 around or dont run them inline. If you had a fuge section in a sump and a cabon reactor before the fuge then I would say no way it would strip the water clean enough to effect chaeto. However the setup u have is a little different since all water going to the chaeto is fully filtered by the carbon. As the carbon gets older it should not effect the chaeto as much. Interesting setup I have never seenor heard of a chaeto reactor. I also personally would not have a fuge feeding into a chiller.