I have a small 12x12x12 (7 gallon) rimless tank I set up just over 10 months ago as a QT for my corals. I've managed to catch red bugs and flat worms in the past by trading corals so I thought it was high time to get one set up to protect the display tank. Problem is, SPS close up, slowly (weeks) starve and die. The system has a small HOB filter (sponge, rubble, and carbon) a heater, and a DIY Rapid LED light.
When I set the tank up I used water from the display in hopes it would speed up the process, I still got a small cycle however. Once the tank had settled in, I placed "test" frags in to see how they would do. As mentioned above, polyps would retract, loss of color, death. The first correction I tried was stop using fresh made salt water, I use red sea coral pro salt and since there was nothing in the tank to consume the alk and calk it was starting to rise quite a bit above the normal range so I started just using a gallon of my display water while I was doing my weekly water change. This helped the calk and alk levels but caused the no3 to rise because during this time I had high nitrates (16 ppm) in the display. Corals in the display were fine so I wasn't all that worried about the no3. More test frags more death.
Next thing I started looking at was perhaps the flow from the HOB wasn't enough for the SPS, so I added a spare mp-10 I had in storage. More test frags, more death. I checked for stray voltage, not exactly sure how to interpret those so I just replace the heater with a new one just in case. Here is the thread with those readings if someone wants to look them over Interpreting Stray Voltage
The next thing I try is with the LEDs, I'm thinking well maybe those aren't strong enough for SPS. I pull out my old HQI light for the bio cube with a 150w 14k phoenix bulb. Bulb was only 6 months old so should be good to go. More test frags, more death. I got to thinking maybe it was too powerful so I went and got another LED fixture and it's been on there ever since. I 'll have to look later at who makes it and the specs, but the LFS that loaned it to me was growing SPS under it just fine.
The only other thing I could think of was a closer look at water parameters, this actually surprised me a little, as I mentioned above, I'm using display water that have very stable #'s as my water change water. Things like calc and alk which test fine on water change day were dropping out to low levels by the end of the week. With no coral at all in the tank to consume those I would have thought water changes alone would be good enough for the QT. Calc would start at 460-470 and drop to 370 by weeks end. Alk would start at 8.5-9.5 and drop to 6.1 at the lowest but usually 6.5-7 dkh. I tried adding a large chunk of live rock hoping that would somehow stabilize things but it didn't. Now I'm dosing by hand twice a day and maintaining a 420ca and 8-8.5 dkh reading. Other reading are stable, 1.026 salt, pH very close to display tank at 8-8.1, temp stays at 78, no ammonia.
I do get a stringy brownish algae in the QT, I've been told it's normal for a new tank to get this and it is supposedly bacterial? I'm assuming it should be gone by now since the tank is 10 months old, but the LFS reminded my I recently added that large chunk of live rock so maybe thats true.
Other things worth noting is if I remove the frag from the QT and put it back in the display, it will recover, polyps come back out and colors come back. I've also tried Zoas and mushrooms. The zoas will die if left in the QT for a month, and the one I removed and put back into the display is alive, but will not grow any further, still one polyp and has been back in the display 3 months. I put in 4 mushrooms on frags and 3 have died, the one left in the QT is faded, not growing or expanding during the day like most mushrooms do, but still alive and been in there since Aug of last year. I added a new test frag 2 weeks ago (birdnest and NoTG) both have faded, retracted polyps. Saturday I removed the HOB filter (the only other electrical gadget) hoping that may have been the issue.
I do weekly water changes, weekly water testing, I keep an on-line log if someone wants to look at these let me know I'll provide a link. Water test was done Saturday and here are the results; Temp 78, 1.026, 420 ca, 7.89 dkh, 8.09 pH., 0 No3, 0 Po4. No3 was 2ppm week or so ago, but still dialing in the carbon dosing. The water change water from the display had .75 ppm No3 so there should be a trace amount in there now. While I was lowering the No3 in the display the No3 was reducing in the QT as well since that is the source of my water.
I am truly at wits end, I'm out of things to try, the tank was used, but know the guy that had it and he kept SPS in there. I, like most humans, can get tunnel vision when trying to figure things out, so I'm hoping for some ideas before I pitch the thing over the fence.
When I set the tank up I used water from the display in hopes it would speed up the process, I still got a small cycle however. Once the tank had settled in, I placed "test" frags in to see how they would do. As mentioned above, polyps would retract, loss of color, death. The first correction I tried was stop using fresh made salt water, I use red sea coral pro salt and since there was nothing in the tank to consume the alk and calk it was starting to rise quite a bit above the normal range so I started just using a gallon of my display water while I was doing my weekly water change. This helped the calk and alk levels but caused the no3 to rise because during this time I had high nitrates (16 ppm) in the display. Corals in the display were fine so I wasn't all that worried about the no3. More test frags more death.
Next thing I started looking at was perhaps the flow from the HOB wasn't enough for the SPS, so I added a spare mp-10 I had in storage. More test frags, more death. I checked for stray voltage, not exactly sure how to interpret those so I just replace the heater with a new one just in case. Here is the thread with those readings if someone wants to look them over Interpreting Stray Voltage
The next thing I try is with the LEDs, I'm thinking well maybe those aren't strong enough for SPS. I pull out my old HQI light for the bio cube with a 150w 14k phoenix bulb. Bulb was only 6 months old so should be good to go. More test frags, more death. I got to thinking maybe it was too powerful so I went and got another LED fixture and it's been on there ever since. I 'll have to look later at who makes it and the specs, but the LFS that loaned it to me was growing SPS under it just fine.
The only other thing I could think of was a closer look at water parameters, this actually surprised me a little, as I mentioned above, I'm using display water that have very stable #'s as my water change water. Things like calc and alk which test fine on water change day were dropping out to low levels by the end of the week. With no coral at all in the tank to consume those I would have thought water changes alone would be good enough for the QT. Calc would start at 460-470 and drop to 370 by weeks end. Alk would start at 8.5-9.5 and drop to 6.1 at the lowest but usually 6.5-7 dkh. I tried adding a large chunk of live rock hoping that would somehow stabilize things but it didn't. Now I'm dosing by hand twice a day and maintaining a 420ca and 8-8.5 dkh reading. Other reading are stable, 1.026 salt, pH very close to display tank at 8-8.1, temp stays at 78, no ammonia.
I do get a stringy brownish algae in the QT, I've been told it's normal for a new tank to get this and it is supposedly bacterial? I'm assuming it should be gone by now since the tank is 10 months old, but the LFS reminded my I recently added that large chunk of live rock so maybe thats true.
Other things worth noting is if I remove the frag from the QT and put it back in the display, it will recover, polyps come back out and colors come back. I've also tried Zoas and mushrooms. The zoas will die if left in the QT for a month, and the one I removed and put back into the display is alive, but will not grow any further, still one polyp and has been back in the display 3 months. I put in 4 mushrooms on frags and 3 have died, the one left in the QT is faded, not growing or expanding during the day like most mushrooms do, but still alive and been in there since Aug of last year. I added a new test frag 2 weeks ago (birdnest and NoTG) both have faded, retracted polyps. Saturday I removed the HOB filter (the only other electrical gadget) hoping that may have been the issue.
I do weekly water changes, weekly water testing, I keep an on-line log if someone wants to look at these let me know I'll provide a link. Water test was done Saturday and here are the results; Temp 78, 1.026, 420 ca, 7.89 dkh, 8.09 pH., 0 No3, 0 Po4. No3 was 2ppm week or so ago, but still dialing in the carbon dosing. The water change water from the display had .75 ppm No3 so there should be a trace amount in there now. While I was lowering the No3 in the display the No3 was reducing in the QT as well since that is the source of my water.
I am truly at wits end, I'm out of things to try, the tank was used, but know the guy that had it and he kept SPS in there. I, like most humans, can get tunnel vision when trying to figure things out, so I'm hoping for some ideas before I pitch the thing over the fence.
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