Reef tank going downhill, could use some help

[reefboxerguy317]

So the past couple months my once thriving reef tank has started to not look so great. This current tank is a 200 gallon that has been running for almost a year, but was a carry over from my previous tank which was running for about 4 years. Lately some of my sps have been doing terrible, all of my monti caps are looking pale and couple have begun to lose some tissue, and many of my acros are are dying and receding at the tips as fast as the tips are growing. I previously used zeovit system for about a year, but I stopped about 6 months ago due to cost and all the time and dosing required.

Current water params are cal 450-475, alk 8-9, mag 1300-1350, ph 8.1-8.3, no3 0, and temp around 79-80. Use an ATI 10 bulb powermodule for lighting. Do have a small diatom issue on sand bed so have been running gfo, will test for po4 as soon as hanna meter shows up but always tests zero using my salifert kit.

been racking my brain for while now trying to figure this out so any additional ideas would be greatly appreciated, thanks.

 

[nixer]

diatoms happen and does meant you have a po4 issue, but most of the time if you have algae your not going to get much of a reading.
what all are you dosing to the tank?
also how much water are you changing?

 

[Emoney]

how old are bulbs?

How fequent do you do water changes?

 

[Surf&turf]

how old are bulbs?

How fequent do you do water changes?

^^^ +1 Whats your water change schedule?

 

[zemuss]

How deep is that sand bed? Was the sand transferred from the 4 year old tank or fresh sand? The SPS that are now RTN are they losing color like the monti? Any other algae blooms, GHA, Cyano, etc..??

 

[reefboxerguy317]

Thanks for all of the responses. Currently i don't dose anything, just running carbon, gfo, and my calcium reactor. Typically do a 20 or 25 gallon water change every 10 days or so using the red sea coral pro salt. Most of the bulbs were replaced couple months ago so those should not be the problem.

Sand bed is around 4 to 5 inches deep, except for areas around my goby/shrimp burrow. All new sand was used.

Other than the diatoms, there is no other algae present. Yeah, the sps with rtn do have faded colors.

 

[zemuss]

Can you get some pictures up for everyone to see? What type of fish do you have in the tank? Do the RTN patterns look like bite patterns? I ask because you say they are still growning but are RTN'ing as fast as they grown. I am thinking you might have a nudi eating the SPS and the Monti.

 

[scrapz]

Have you checked for stray voltage? Recalibrate your refractometer, it may be off.

 

[VegasRick]

Have you checked your RO water? DI resins may be exhausted.
With all the parameters in range and stable makes it hard to diagnose. Is there any metal that might be rusting or leaching into the system.
I personally keep my alk a little higher than that.

 

[reefboxerguy317]

I can try to get a picture or 2 up when I get home. The issues with the acros looks like alk burn from too high of alk when using low nutrient systems, except haven't used zeovit for awhile now.

As far as fish I have never seen anyone nipping on the sps, not to say it doesn't happen when I'm not watching. I have a couple tangs, anthias, clowns, mystery wrasse, swallowtail angel, coral beauty angel, and 2 foxfaces. All of these fish have been in the tank for awhile, all of them before I started having problems.

 

[reefboxerguy317]

I change my DI resins as soon as I notice it gettings above 2 or 3.

If there's any metal or anything thing like that in the system I have never noticed it when working around the tank.

 

[zemuss]

OK how about the electric current issue? Do you put your hand in the tank and if you do does it tingle?

 

[Murfman]

Coral Beauty could be nipping at the new polyps. I had a Flame Angel that decided one day he liked the taste of coral polyps. I had him for over 2 years before he got "hungry" for the polyps. I am not an expert but have heard a lot of people having issues using TOO much GFO, when they 1st start using it. They describe the symptoms you are having.

 

[zemuss]

I also have seen Blue Hippo Tangs eating Chalice corals. I was actually at the LFS and they guys was saying he was having a hard time with Chalice in a display tank. I told him it was because your Blue Hippo is having a feast on the Chalice!

 

[Znut Reefer]

What changes have you made in the past few months?

 

[skinz78]

I am wondering if your Alk test kit may be bad? Do you have any buddy's near by that you could compare your test kit findings to theirs?

 

[SaraB]

Agreed, maybe a bad Alk test kit so borrow or get a new one to compare readings.

Also, what are you testing your TDS with? If it's inline, get a hand held to confirm it's reading accurately.

Check the calibration on your refractometer too.

 

[Mr.Firemouth]

Agreed, maybe a bad Alk test kit so borrow or get a new one to compare readings.

Also, what are you testing your TDS with? If it's inline, get a hand held to confirm it's reading accurately.

Check the calibration on your refractometer too.

Sara's on the money here for your conditions.
I would assume right away that it is an Alk issue. 2 reasons: Alk burns on the corals with color fading, and the diatom on the sand bed sounds like brown form of cyano related to low alkalinity readings. If you recently changed your GFO you could lower Alk. Alkalinity and phosphates have a strange relationship. :-)

 

[reefboxerguy317]

Thanks again for all the responses.

One of the first things I suspected was alk, but I checked that against actually 2 other lfs in my area. Between the 3 of them alk tested anywhere from 8 to 9. I have my water tested at lfs every saturday to check against mine, so I'll see what there tests say later today.

Refractometer was calibrated and that was accurate, and I use one of the handheld hanna tds meters, also recently calibrated. You can see I get little anal about testing and calibrating stuff lol.

Maybe adding gfo after stopping zeovit is the cause, it is honestly the only thing new added to the tank in the last 6 months.

 

[skinz78]

I have heard of people having issues when they stop using the Zeo, why did you stop?