High Redox

[jdjeff58]

I've been monitoring my redox for about 3 weeks. When I put the probe in for the first time it started to climb and settled out at about 350-360. I have had a couple of decreases since then and I was able to get it to recover. One cause was a clogged skimmer air line and the other was a faulty titanium heater. The heater failed (quit working) and my redox was low. When I pulled the heater out the redox went back up. I think the heater may have had a leak. I do have a grounding probe.

Anyway, since the heater incident (two days ago), I've had an algae bloom. My redox is now reading 420. My pH went from 7.8 to 8.0 in a matter of hours. Does this make sense? It isn't making sense to me based on what I've been reading about ORP. I thought pH and redox were inverse of each other. I cleaned the tip and checked the calibration on the redox probe. I'm still waiting for it to climb back up.

I was reading somewhere that algae on the probe tip will cause it to increase. So couldn't an algae bloom cause it to go up too?I'm sort of concerned since some of the articles I'm reading are saying that 400 and above is a dangerous level.

It's a new tank (6 weeks) and I really haven't had much of any algae build up until now. It's light green in color and spreading around the sand and rock as well as the glass. It's not all hairy or anything, it's just kind of fuzzy. Nothing died. I added two small clowns a week ago in the display and a sally lightfoot in my fuge that just molted. I have a handful of snails and hermits in fuge and display.

I'm not concerned about the algae as I'm aware this is normal for new tanks. It's the redox that's got me wondering.

Thanks

120 gal
ammonia 0
nitrite 0
nitrates 2.5
calcium 450
alk/dkh 2.97/8.3
temp 79
sal 1.024
ph 7.8-8.0
phosphate 0

[Billybeau1]

I wouldn't start worryng unless it gets over 450 mv

If you suspect your heater leaked something, you may want to run a good quality carbon to soak it up.

For the algae, check your phosphate levels. They may be slightly elevated.

Are you injecting ozone ?

And yes, pH up, ORP down.

[jdjeff58]

Originally posted by Billybeau1
I wouldn't start worryng unless it gets over 450 mv

If you suspect your heater leaked something, you may want to run a good quality carbon to soak it up.

For the algae, check your phosphate levels. They may be slightly elevated.

Are you injecting ozone ?

And yes, pH up, ORP down.

Hey..thanks for the response. My phosphates are 0. I have only done a couple of feedings and except for the first feeding ,I have really been careful. The tank is only 6 weeks new.

The heater I was using was a Jalli 500w titanium. The first one burnt out and the replacement burnt out not long after. I believe they are flawed in that they are shorting out because of water leaking in. I don't like 'em. I replaced it with a Hydor 400w glass heater and it actually controls much better.

But in any case, I'm still waiting for the redox to come up after I cleaned the probe yesterday. It may have been dirty as it is creeping up much slower....it is now at 302. I also did a 10% water change yesterday and this reading makes a little more sense. I also use DI water from a Spectrapure maxcap 90.

But the question still remains, could an algae bloom effect the redox in the upward direction? How about the pH?

Thanks again.

[Billybeau1]

Algae on the tip of the probe could cause a false high reading, yes.

I'm not sure about the pH.

Also , water changes will temporarily drop ORP as the ORP of New salt water is around 240 mv or so.

[jdjeff58]

Originally posted by Billybeau1
Algae on the tip of the probe could cause a false high reading, yes.

Yes...that part I get. I don't want to beat a dead horse, but I'm just sort of curious of what happens during an algae bloom. To me, there would be increased photosynthesis which would result in changes in pH and ORP. Am I on the right page with this thinking?

[Billybeau1]

Photosynthesis raises pH but should lower ORP slightly.

[jdjeff58]

Originally posted by Billybeau1
Photosynthesis raises pH but should lower ORP slightly.

Ahhh...ok. Thanks again.

[Boomer]

I was reading somewhere that algae on the probe tip will cause it to increase. So couldn't an algae bloom cause it to go up too?I'm sort of concerned since some of the articles I'm reading are saying that 400 and above is a dangerous level

I do not see the word Ozone in your post. Are you using ozone ? If not, it does not matter how high the ORP gets. However, you will never see 400 or higher without ozone. So, it is the probe if that is the case.

[jdjeff58]

Originally posted by Boomer
I was reading somewhere that algae on the probe tip will cause it to increase. So couldn't an algae bloom cause it to go up too?I'm sort of concerned since some of the articles I'm reading are saying that 400 and above is a dangerous level

I do not see the word Ozone in your post. Are you using ozone ? If not, it does not matter how high the ORP gets. However, you will never see 400 or higher without ozone. So, it is the probe if that is the case.

No ozone....and from what I've read about this subject so far..I'm not going to go down that road. I'm strictly monitoring. It has actually paid off a couple of times. I really only got this probe figuring it might come in handy. I ordered it with a Profilux controller so I would have something to look at other than temp, pH, and conductivity. I've just been watching it to figure out how it acts. I'm into this kind of stuff since I have been involved in process loops in my work.

That's what the problem appeared to be....dirty probe. It has been about a day and a half since I cleaned off the probe and my reading has crept back up to 306. What complicates this slightly is the recent water change and as of yesterday I had to replace my skimmer. I'm suspecting these two things to be the cause of the 306 reading. I'm still on a learning curve so I can get a little panicky if something is not behaving according to the articles I have read.

I have seen a few articles about redox and although they talk about some of things that decrease redox, they don't say a whole lot about what increases it.....other than ozone. I did read that algae on the tip will make it go up, which got me thinking that an algae bloom might cause the same thing.....maybe not as abrupt. It doesn't look like ozone for controlling is very popular....at least among the experts writing about it.

I know my tank is kind of young and it will most likely take some time for the ORP to give me some sensible readings. From what I've seen so far, it does like to hang out between 350-400. That's why the increase had me asking questions.

[Boomer]

OK, those decreases are normal. Many things can cause it to lower itself. At 350-400 is a good value without ozone and if you can approach 400 you are doing great without ozone. ORP is not a very easy subject to understand. Randy himself has said he will never understand it

Did you see this

ORP and the Reef Aquarium
http://reefkeeping.com/issues/2003-1...ture/index.htm

[jdjeff58]

Originally posted by Boomer


Did you see this

ORP and the Reef Aquarium
http://reefkeeping.com/issues/2003-1...ture/index.htm

Yes....I've read over that a few times, digesting a little more each time. There are a couple of other articles I read that were much less in depth. Opinions seem to vary, at least on the necessity of measuring ORP. Since I paid for the probe and the interface card along with my controller, I'm going to make believe that it's really important to measure ORP. Opinions concerning the use of ozone or other means of raising ORP look to be pretty much across the board. Opinions on the acceptable levels vary slightly. I think being able to monitor changes is a pretty useful tool. My probe so far has shown me a couple of things that caused me to investigate (and find) 2 problems associated with the drop in ORP. The little valve on my skimmer that controls the air intake was plugged with salt creep. My ORP caused me to look around and that's what I found. I unplugged it and the ORP came back up. I also noticed another drop in ORP and found my heater to be causing it.

I think the fact that it acts as a red flag makes it a very useful tool. And that was really my intent when I got it. I realize it can throw you some curveballs, but at least it gets your attention.

[Billybeau1]

Originally posted by jdjeff58
I realize it can throw you some curveballs, but at least it gets your attention.

Boomer is a good curve ball hitter .

And fast balls, and sliders, heck he can even hit a knuckleball when he has to.

[Boomer]

I though this was a reefing forum and not Baseball forum. Am I on the right forum tonight

[Billybeau1]