Sorry to hear that...that's awful.

Just a theory...

Shutting the skimmer off at night allowed the oxygen level in the tank to drop to deadly-low. Fish died....then the skimmer came back on to find a extra jolt of death in the water and foamed over.

Skimmers supply O2 to the water as well as remove nastiness. This is critically important at night when no photosynthesis is occuring. (unless you have an opposite-light-cycle refugium...which can help)

Once you are up to it, read this...

http://reefkeeping.com/issues/2005-08/eb/index.php

Sorry to hear about your skimmer problems and subsequent losses. This is exactly the kind of thing that prompted me to install a float switch into my skimmer cup over the weekend. I've had a couple episodes of my skimmer overflowing for no apparent reason (one time while on vacation leading to some nasty damage). I don't know if it's a BK thing because I get the same intermittent fizzing then skimming thing you described earlier as well. I'll never run a skimmer without a float switch in the collection cup again.

Don't bow out yet. Take it as an opportunity to install some new backup hardware - new toys are fun ;)

I've read numerous references that O2 is not strongly affected by protein skimming.

From the article you've referenced above:

Airstones and skimmers appear to be a very effective means of oxygenating small water volumes. Their effect on larger water volumes appears to be less. While the effect may be relative, the larger tanks and systems described here utilized powerful skimming or air pumps, and to gain an equivalent amount of oxygen as occurs in small water volumes would likely require air pumps or skimmers far larger than those commonly employed by aquarists. This includes data from a coral farm where very large commercial sized skimmers and high surface area/volume ratios failed to produce water even nearly saturated with oxygen at night with a heavy coral population.

Thanks untamed, I actually was just running the skimmer at night and not during the day to avoid low oxygen levels at night. However I did just figure out the problem and it was a result from low oxygen.

I remembered I did the final programming on my controller yesterday, what I wanted was the skimmer to act as a timer and only run at night but I also wanted it to turn off during a "feeding pause" because I would be feeding the corals more at night. In addition I wanted it to stay off for another 30min after the feeding pause ended. I used the programmable logic to to combine the timer with a delay on set to 30min and then all I needed was the timer to shut off during a feeding pause but I couldn't do this with the programmable logic. So I noticed a check box under the timer which said something like "active then feeding pause", now keep in mind that profilux language seems to be mostly translated from German so it's not always clear, I automatically assumed that checking this box will insure the skimmer will shut off during a feeding pause. Similar check boxes are attached to other processes and I've used them before with success.

Unfortunately I was wrong, by checking that box I told the controller to activate a feeding pause while that timer was active and for as long as that timer was active! So last night at mid-night, while I was sleeping, all my pumps turned off and 30min later the skimmer turned on, which overflowed with the higher sump level. The pumps remained off until noon today. The fact that this happened over night with all the livestock I have must have completely diminished all the dissolved oxygen in the display while the skimmer helplessly filled the disconnected sump with foam.

So Mr OM, you were 100% correct, it was an engineering problem. A problem resulting from the stupidity of this engineer who didn't check his programming which resulted in the death of very creatures I designed this tank for. I take full responsibility but the one thing that blows my mind is that the profilux will not allow you to set a feeding pause longer than 20min yet it will allow a timer to activate one for as long as you set that timer for. That is one dangerous check box, users be warned.

I think you mentioned that your clams spawned a couple of weeks ago...maybe that "stuff" also had something to do with your problems...along with the pumps being off and your skimmer not working very well .It all added up.

Ai ai ai Steve!! This is horrible news!! :eek: :(

Let me know if I can help you out at all. Remember, I'm only 5 blocks away. ;)

Go
 

this is a noob question. How do you measure the level of nutrient in your tank? How do you know if it is high or low?
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ASCARI

By nutrients we mean nitrate and phosphate specifically. In the case of phosphates, we can only measure inorganic (dissolved) phosphate. Standard test kits are not very accurate in the low range. I would use Lamotte, Hach, or D & D Merck. SeaChem and Salifert are two of the better hobby-grade (cheaper) kits on the market.

Go
 

Sorry to hear your lost.


What level nitrate is considered high nutrients?
________
Marijuana sativa

Nitrate levels over 25 ppm will adversely affect coral health. Anything above 10 ppm will cause nuisance algae growth. I would shoot for 2 ppm.

Phosphates should be 0.05 ppm. Corals will be adversely affected if it goes above 0.10 ppm.

Nutrient levels on natural reefs are zero, but they are always bioavailable. Captive reefs don't have as much organic phosphate and nitrogen available due to a lack of plankton. As a result zero nutrient tanks are only suitable for sps corals. Good lighting and heavier feeding must also be implemented.

Sheez Steve. Sorry for your losses. Figured it had to be something besides the skimmer & oxygen, as many dont run skimmers and IMO, the overflow/down stack provides more than enough o2.

Sometimes I look at my controller, {RK2} and wonder.

I know what you mean Doug, you spend all this money on these devices that are suppose to make things easier and safer but all they really do is add more complication which can result in more human error. I tried to make this system as simple as possible to avoid these kinds of things but I guess I should have maybe left the controller out as well. Oh well. Your RK2 is probably a little better since it's not translated from German, things are probably a little more clear.

It still makes no sense to me, "when active then feeding pause", wouldn't one assume this to mean if device active then include in feeding pause? The other way doesn't make a whole lot of sense.

Anyways, I haven't decided what to do as far as selling or staying in yet. I feel bad about the losses and there's a lot going on in my life right now so much more involved than this last disaster, but knowing the exact cause really helps. If it was up to me I'd probably just sell it and start up fresh a few years down the road with things stabilize. However like most of us I have a better half who always seems to have 51% ownership and gets the final say and she's against selling so.....

Since I know the cause I decided to continue with the experiment, the skimmer is set back to the 0.5 duty cycle. I'll have to figure out a way to program it the way I want it but for now it's just a timer combined with a filter so it shuts off during a feeding pause but doesn't have the extra delay I want. I will continue with things as planned and report back with results. I'll be testing Nitrate and Phosphate weekly in an attempt to track results but likely the real results will be all visual.

well, this sucks, how are the corals doing now? it always sucks when we loose stuff, but for the most part I would rather lose fish than corals, even though I would still be choked losing fish I had a long time.

as for deciding weather you stay in or not, this is a relitivly minor setback, if the corals and rock is fine, you can do a big water change to speed up the stability. It sounds like you have figured out what caused it and it is a preventable issue so there shouldn't be a repete. when my heater stuck on and wiped out everything, including my rock (was nutrent pluged after the crash) I almost stopped also, as it would have cost about 5 to 7K to replace the corals, rock and fish to exactly how they were, so I know how you feel.

Steve

Thanks Steve, the corals are doing fine, well some of the LPS are still unhealthy but basically this little disaster had no effect on the corals or inverts.

To me it's not about the money, but some things can't be easily replaced. The seahorse and lion together were, without a doubt, the center piece of this tank. The lion could be replaced with some effort on training a new one but the seahorse will be especially hard to replace since I haven't even had another importunity to buy a mate since I purchased the original. As far as I remember it was a special captive bred type from Australia and from my experience the only type worth keeping and the only type I will keep. In particular everything in the tank was chosen around the seahorse and to loose that particular piece of livestock results in the tank making little sense to me now. It also just sucks to loose stuff like this when you're making efforts to improve the tank.

Normally I wouldn't say this but... listen to your wife :)

sorry wasn't trying to make it about the money, for me that wasn't the issue either I was just trying to show the size of loss I had. for me it was about the corals, I had a tri color milli that was almost 24" dia and about 3 other very large corals which would have been impossible to find in that size. I can relate to losing the showpieces of the tank you designed yours around a couple fish, I did mine around corals and my fish were secondary. Anyways now you have the opertunity to change a few things or find something else you wanted that maybe wasn't compatable with what you had... always got to look at the bright side, is my way of thinking.

Steve

We learn daily, I have never been a big supporter of reef controllers but prefer to stick with PLC's and let a reliable source program it, I have a controller in the works that will give me a bunch of programs to choose from but am still paranoid that during selection there may be a glitch that I may be unaware of.

Stephen, take the issues that you find,use you resources to find a solution and let them know, the industry will be better for it.

Update
 

Both nitrate and phosphate are up slightly, previously both were at undetectable levels, now they are some what detectable.

Nitrate: somewhere between 0 and 1ppm so we'll say 0.5ppm
Phosphate: around 0.01ppm

I've also been feeding more and I've noticed a slight improvement in LPS health. Seems to be working.

It's strange the nitrate and phosphate would climb even though you aren't feeding fish anymore, and the bioload is subsequently lower. You must really be feeding those corals.

Well yeah and I got two new fish I'm currently training and two originals that survived so overall I'm using quit a bit more food. Plus it's not much of an increase, before it was without a doubt zero on the test kit, now it's just barely showing a possible detectable concentration.

Good to hear some survived.

What do you train your fish to do?

I wish I had trained mine to swim into a small separate tank for feeding (and capture if necessary)...sort of the way that the aquariums train the whales to allow for examinations....

:lol: Just to eat frozen and eat quickly to compete.

No jumping hoops I guess?

What kit are you using to test phosphate anyway? Unless you're using a Merc kit or comparable, such a low reading is probably inaccurate.

Elos, the next reading above zero is 0.01 then it jumps to 0.1

Ya, likely not too accurate at that low number, but at least you know there is probably "a little bit". I find if you compare to a Merc kit both Elos and Salifert will show lower readings than the Merc.