Mysterious Problem in my tank

digitalis · 04-29-2007, 04:09 PM

I think I may have finally found my mysterious fish-dying problem. I lost a cleaner shrimp, and my Scolymia is bleached and anemic looking. I talked to Jim @ MWC, and he asked if my salinity was on.... I said it's at 1.022, why? He asked how I checked it, and I told him I used a Refractometer. He said they're junk. Said he uses the bobber type Hydrometer. I had one, but it was a mini one from Petco. He sold me a full size laboratory grade one for $17.99. I took it home, and checked my tank. Refracto, 1.022. Bobber, 1.018. Needless to say, I think I may have found my problem. Hopefully everything recovers alright. I moved the Scolymia out of direct light to hopefully recover some from its bleaching.
I told him I thought refractos were good, and he said no, they're junk.

I always thought it was good. Come to think of it, I have had problems since I changed from my swing-arm type to the refracto. I just checked the bobber against the swing arm. Bobber says ≈1.021, and the swing says ≈1.021.

Swing arm was right all along, and the refracto (that I was sure was right) was wrong.

You learn something new every day.

Parasite · 04-29-2007, 05:57 PM

When was the last time you calibrated the refractometer? You should calibrate it quite often.

Brett

digitalis · 04-29-2007, 06:29 PM

When I got it I calibrated it, and it showed different than the swing-arm. I never bang it around, it always stays in its plastic foam lined case. I just checked it yesterday when I discovered this, and it's right on. Now if it's right on, and the bobber is scientifically Laboratory Grade, and the bobber is right, why isn't the refracto. And why does the bobber match the swing arm nearly exactly.

bklynmet · 04-29-2007, 07:37 PM

You need to do a two point calibration with refractometers... the zero oint is easy - just ro water works... here;s an article for the high point, by RHF
http://reefkeeping.com/issues/2004-06/rhf/index.php

digitalis · 04-30-2007, 03:33 AM

How do I set 2 points with one adjustment screw?

Quote:

Originally Posted by bklynmet

You need to do a two point calibration with refractometers... the zero oint is easy - just ro water works... here;s an article for the high point, by RHF
http://reefkeeping.com/issues/2004-06/rhf/index.php

grallster · 04-30-2007, 09:17 AM

I seriously doubt that is what was causing your fish to die. Some people keep their tanks at 1.018 at all times. That low of salinity is more harmful to corals than fish IMO.

Adnuces · 04-30-2007, 05:47 PM

fish can handle low salinity levels and actually hyposalinity is a method of combatting ich. The low salinity wouldn't be a problem as it happened gradually over time. If it happened suddenly then yes it could be a problem. Your refractometer should be calibrated as Joe said to two points. Provided that you use the same measurement tool consistently and it is calibrated often the difference in measurement shouldn't be an issue.....It would pose a problem if you if it suddenly went out of whack....and you were doing a massive water change or something....and your replacement water was something like 1.035 and your tank was at 1.018, now that could pose a problem

digitalis · 04-30-2007, 06:37 PM

Well, My Xenias died the second day they were in the tank. My Trumpet coral just split on 3 heads, and the one just died. I have killed 2 anemones, and my Scolymia is dying. Does that much coral damage indicate water problems?

Tasher80 · 04-30-2007, 09:35 PM

The way you calibrate would be to use RO/DI waster for the zero calibration and a 32PPT solution. That way you can check both.

lostwhirley · 04-30-2007, 11:13 PM

I too would be very suprised if it was because of your salinity. IMHO, and I don't mean to offend, but I think it's because of your temperature.

tangwhispr · 04-30-2007, 11:37 PM

Personally I use a pinpoint monitor, but for years I used a cheap bobber one and then a refractometer, and they worked fine....don't be sold on gimics, have you tested all your other params? or have you done a water change?

digitalis · 05-01-2007, 03:29 AM

I do a 12 gallon water change (10%) at least every 2 weeks, and my temp is at 76. pH is right at 8.2. Calcium is a little low at about 200-250, but Jim said his tanks always ran 200 until he got his calcium reactor.
I was running my protein skimmer for a week, and never saw any skimmate coming out. There's a huge bubble tower but no skimmate. I added some Reef Essentials, and the next day the skimmer was full of purple water (the color of Reef Essentials). I thought maybe I was skimming all the good stuff out of the water, so I unplugged it. I've been running 2 days without it now. I don't know what else to try. The skimmer is an ETSS 800, rated for a 180-400 gallon tank. Mine's a 125.

grallster · 05-01-2007, 08:54 AM

What are your other tank parameters? Ammonia, nitrite, nitrate, phosphate? What is your alkalinity? With that low of Ca, the alkalinity might be dangerously low too. Do you use RO water?
If you were only running a skimmer for a week it might not be broken in yet. I'd turn it back on.

digitalis · 05-01-2007, 04:45 PM

Ammonia, 0
Nitrite, 0
Nitrate, 2.5 +/-
Phosphate, don't have a test kit.
I use RO Water.
Not sure on alkalinity, it hasnt been a problem as of yet. But I haven't tested it for a while.
I've been using the skimmer since September or October, but for a week, it didn't take anything out.

Quote:

Originally Posted by grallster

What are your other tank parameters? Ammonia, nitrite, nitrate, phosphate? What is your alkalinity? With that low of Ca, the alkalinity might be dangerously low too. Do you use RO water?
If you were only running a skimmer for a week it might not be broken in yet. I'd turn it back on.

Adnuces · 05-01-2007, 05:23 PM

Temperature and ph, temperature will melt xenia faster than you can say bubblegum, anemones need pristine conditions with virtually zero nitrates and excellent light. Most anemones you buy are already checking out as most have already lost their zoanthelle during shipping.....I keep my temp at 78 night and 80 daytime. I don't have a ca reactor and keep my ca at about 420 and alk at about 4 meq/l .......your ca level should be higher than that if you are doing water changes weekly.....these changes should also be taking care of any trace elements and magnesium etc. Your lack of skimmate should be addressed you should be pulling junk out of that water ......I would check your adjustments on the skimmer.