[prow]

ok let me give my set up first.
tank 72X18X20 115ish gal with about 150lbs live rock and a 1/3" sandbed. on stand with canopy.
45gal sump with 24X12 refugium with miracle mud and caulerpa.
10gal sump with ASM G-3 skimmer
return pump for both sumps is a sedra 1200gph pump
flow in the main tank 3 maxijet 900's on a wavemaker, tunze streammer pump with controller alternating between 1850gph and 1000gph ish.
lighting is 6-80watt T5's
lighting in sump is 1-18watt T5, for past 2 weeks, other light broke getting new one soon.

tank water levels is;
NH3/NH4....0.0
NO2...........0.0
NO3...........0.0
phos..........0.0
silicate.......0.0
temp..........running 80/81-82/83 (little high)
ph..............AM 8.18 PM 8.33
Ca.............410
alk.............3.09
O2.............6ish hard to tell with this salfert test kit.
salinity......34

the story, well try to make it short. about two months ago i had two wrasse die basically over night. had them for 3 months noticed they were breathing kinda rapid the night before they died. but were not stressing at that time. after they died i thought it was my O2/CO2 because tank in a room not much air flow and i have a canopy. tested my O2 i think i read it to be close to two. i put air stones and openned up the canopy and stand doors. plus got some air flow in the room. i put in 6 greenbanded gobies, very small about 1/2", 2 weeks ago, they are doing fine. still in the tank with no issues. about 2 days ago
i put in a percula clown that i have had in another tank for about 4 years. i noticed today he was breathing very rapid and in obvious distress. took me a little while but caught him and put him in the QT i have had set up for a while now. looks like his eye are a little bubbled and he is still breathing rapid. dont know if i got him out in time or not, this just happend. he is still stressed in the QT resting on the bootom. hope he makes it but what could be the issue here. the greenbanded gobies are ok just dont know what it could be, any idea???

o the tank has been going for about 14 months. 6 onths with just live rock followed by 6 omnths with various snails (all still in the tank) then the past couple months had the wrasse (the first fish) greenbanded doing good tell now possible death of 4 year old percula clown from one of my other tanks.

[The R/C Man]

Wow that is a tough one..... Unfortunately I don't have any Idea where to begin. "When in doubt swap it out" the water that is. There are many people that conduction large water changes with no ill effects. Maybe you should try to do a few large water changes over the next few days. Hopfully that will help....

Do you have a calcium reactor on the system? If they sit idol for a period of time they can cause issues. The same is true for the PH being to low in the reactor.....

[smidoid]

Are you sure about those tests? The nitrite and nitrate look "too good". It may just be me, but when something's this perfect (in a running system) it makes me think twice about the tests. Just a thought - you might like to retry the test on your QT.

Also - why are you using a skimmer with Miracle Mud? I don't have it so I can't tell, but the blurb says you don't need on and using it can be couterproductive since it shreds the plankton that thrive in the mud. Second, are you using the 24/7 photoperiod as suggested? The fact that one of your lights broke might be a clue. Perhaps the Caulerpa has bombed slightly releasing toxins into the system. I hear that a bad Caulerpa crash can bring down an entire tank. May be worth looking into that some more.

[The R/C Man]

Stray voltage in a tank can stress inhabitants. If you have multiple power heads in the tank there is a potentional for that to occur. Stress reduces a fish’s immunity. Just another thought....

[prow]

well teting is right have many test kits and probes, double checked everything. did a full round of testing 4 times during the past few days. recalibrated all monitors and cleaned probes and double checked the monitors with a testing kit. i have no bio in the tank other than about 50 mixed snails and a cleaner shrimp, plus the 6 greenbanded gobies and a mandrin. no corals. few feather dusters. year without fish no detectible nitrates or nitrites no so suprising.
yeah they say dont use a skimmer but the mud was not effective, always had nitrate present with out the skimmer, this with a very very light load. so i added the skimmer about 3 months ago. i did get the nitrates to zero before adding fish. no noticeable change in wtaer chemistry after adding fish. so now i use the mud more like just a substrate to anchor the macros. not counting on it to do anything like they claim. no clacium reactor, i am using kent two part additive. dosing about every 3-4 days. nothing added a couple days prior to adding any live stock.
i looked at the mandrin and greenbanded gobies, all breathing normaly act normal too. well as normal as a fish can be, anyway. i just dont get it. eerrrr soooo soo soso frustrating.
the light in fuge i dropped and broke the bulbs, just need to replace them. i have the 18 watt T5 for back up. yes the light has always been on 24/7. the caulerpa could be releaseing things but dont really think so. i just dont see any difference in the looks of the caulerpa. water is cystal clear.
stray voltage could be the cause. i dont feel a shock in the tank water but that doesnt mean its not there. what is the best thing to get to test for stray voltage? i think i will do like 4-50% water changes over the next 4 days wont hurt.
the clown seems to be doing better in the QT but still not active, just sitting in one spot. still breathing rapid. although doesnt look as rapid. he is also staying upright with no little effort, this is a improvement. was struggling to stay up right when i first moved him into QT.

[prow]

o one other thing, i order a couple blue head tilefish a yellow clown goby and another percula clown to buddy up with my old clown. the tilefish and percula clown are in QT. the yellow clown did not come instead i got a maroon clown, he was in QT only for a week before i needed the QT after this stuff happend. the maroon is now in a plastic bowl with cover and holes drilled all through it. put in after getting percula out. he is doing fine so far.

[The R/C Man]

I am not an expert or anything but I would think a multimeter should be able to read stray voltage in the water. My guess is to set it to A/C and put the probes in the water. If you get a reading, I would try to unplug individual power heads one at time to find the culprit. If there is one.... Let us know what you find out....

[smidoid]

A meter won't read stray voltage between the probes Greg as the water is essentially a short circuit. (Pure water isn't a conductor, BTW, it's the impurities that make it that way).

You would measure AC voltage - putting one probe in the tank being careful not to get yourself wet and the other one in the Neutral line. Preferably set the test with the power OFF and stand back when you turn on to take a reading. Can't be too careful!! There are a few more tests you can do, but that's the most likely problem.

A faster method might be to put an RCD breaker on the inlet. IF there is some leak then the RCD should pick it up in milliseconds.

The nitrate still intrigues me. I don't see how a skimmer would remove it as it's not part of the foam fractionation removal process - nitrate (and rite) are disolved chemicals (very simple molecules) and shouldn't really be affected in the same what that complex carbon based organics are. [Now watch someone prove me wrong! LOL!]

[The R/C Man]

Thanks for the correction Marc. Your explanation makes sense to me!

From what I have read, the skimmer doesn't remove nitrates. It does however remove the dissolved organics before they have a chance to break down by the denitrification process. So the outcome of the skimming process is less nitrates.

Marc where are you located in the UK?

[smidoid]

Yes Greg, that's partly true - but most of the ammonia we're dealing with (the top of the chain) is directly excreted from the fishes gills. DOCs are organic - carbon based - and not going to breakdown into ammonia unless they contain nitrogen atoms too. (Not that this is my area of expertise). Most of the waste DOC probably comes from decaying food - so if we don't overfeed, the need for skimming is reduced.

About.com has a series on protein skimming (with reference to Jaubert's skimmerless system) here:
http://saltaquarium.about.com/cs/pro...a/aa052200.htm

They also have a poll (http://saltaquarium.about.com/gi/pag...l_id=794603363)

which suggests that most people either use either LR/LS combination (that's what I'm culturing right now - without fish!) or a hang-on bio-wheel (http://www.marineland.com/science/biowheel.asp). I'm considering driving a biowheel too just for good measure. LOL!

You can almost see my house on Google! Just go to http://maps.google.co.uk and enter TS8 as the search term - zooming in and out will give you an idea.

[The R/C Man]

Wow you are way up there! lol. I was just in Cambridge a couple weeks ago and will be passing through again in June that is why I was wondering.... You must be a good 6 to 8 hour drive hugh?

[smidoid]

Google will tell you the distance and drive time too! All hail google.

Cambridge to my house is (about) 198 miles and according to Google, would take about 5 hours.

[The R/C Man]

If it wasn't so far I was thinking that we could have gotten together and talk tanks.... Oh well!

[smidoid]

Pity. Well, if we're every attending somewhere a bit close (for example a exhibition in London (England) we could meet up then.) It'd be a pleasure.