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Corals receding - slow tank crash (1 Viewer)

chemsol

Senior Member
Joined
Jan 26, 2009
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435
Location
Inver Grove Heights
Alright, I give in...

Had good luck with my tank up until I left on my honeymoon in April. There was a partial tank crash I'm guessing due to high alk and one of my lights going out.

Since then, I have been battling to get parameters in check with frequent water changes, adjusting dosing, etc. Things get better for a couple weeks and all of a sudden, another coral starts to die. I am losing chalices, montipora, birdsnest, and other sps and lps. I have tested for Phosphate, Nitrate, Alk, Calc, etc. Here are the latest values holding realitively steady for the last month.

Alk - 8.5 Salifert and Red Sea
Calc - 460 Salifert and Red Sea
Phosphate - .08 read with Hanna Phos Checker (non low res)
Nitrate - Undetectable with API kit
PH - 8.2-8.4 using to PH monitors through Apex
Mag. - 1300
Temp min. 78.5- max 79.0

The tank and sump are approximately 200 Gallons. I do a 20 or 30 gallon water change almost every week.

Equipment

Skimmer - I-Tech 200 (rated at 200g)
BRS high capity GFO (approx. 1 cup)
2 x 6105 Tunze and 2 evo Koralia 1400
30 gallon sump

Dosing
Combo 3 x BRS or Drew's dosers with BRS 2 part
Alk
Calc
Mag

Salt
Seachem Salinity

Lighting

2 x 100 watt LED multichips as primary
2 x 30 watt LED Actinic

Can anyone make suggestions of what to change or try next? I will be going the waterfall algae scrubber route but can't afford to build it at the moment.

All comments welcome!
 
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How often do you change out that GFO?

BRS calculator says 1.56 cups of high capacity for 200 Gallons. If I were using only 1 cup, I would want to change it out every 2 to 3 weeks max.

If you are going 4 to 6 weeks, then phosphates slowly creep up until you change the GFO and then by the next morning they are down to zero. Any fast change, even a good one, is bad in a reef tank.

If you are up to speed on that, then I'm with you, no idea. Maybe a pest eating them at night, maybe do some flashlight hunting.

I'm sure others will ask about stray voltage, I have seen comments both ways on the impacts of this, I have no real opinion or experience.

One more thing, chloramines? If the city you live in uses them, then it is possible that at every water change, you are adding ammonia to your tank. See the link started by "BC UNITED", 'FAZZ' gives a list of cities in MN using chloramines.

Good luck, sir.
 
I'd also adjust the dosing and get that alk down more like 7.5 and see if that helps especially if acros are receeding from the base up. I can always tell when my alk is creeping up just by the slightess amount of recession on the encrusted bases of a few corals.

I'm sure you have already but playing around with LED too. Could still be too much for some.
 
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Good info!

I was running the recommended 1.56 cups by BRS prior to the crash. After losing half my coral and reducing the amount of food 4 - 2 cubes per day, I decided I would run the GFO and test regulary 2 x per week to try and reduce the strain by adding too much GFO on change. I was changing every 1.5 months or when testing indicated an upswing in Phosphate. At no time have I ever achieved a 0.0 reading on the Hanna checker. The lowest I have seen has been .02.

I'm on well water that is pre-filtered for iron (separate filter) then by a water softener. RO is 2 mechanical filters, then 1 carbon, plus DI.

No critters that I have seen during night checks. The corals tend to swing in health where they recede and then come back so it wouldn't appear to be critter related.

I followed the stray voltage thread and removed a powerhead and heater that were suspect. My fish appear to all be healthy and I would suspect the voltage would affect them more than the coral.

Thank you very much for your comments. It really helps keep me focused on the problem.
 
I'd also adjust the dosing and get that alk down more like 7.5 and see if that helps especially if acros are receeding from the base up. I can always tell when my alk is creeping up just by the slightess amount of recession on the encrusted bases of a few corals.

I'm sure you have already but playing around with LED too. Could still be too much for some.

Yes, the acros have been receding from the base-up. I'll see about reducing the alk slowly. I'll also reduce the light cycle to see if that has a positive affect.
 
some thoughts -

Have your water checked before and after a water change at an LFS or someone else including salinity/Sg

I dont see a value for Mg; might want to test that too.. also dosing regulary of Mg is not needed... if dosing dose really low and add more manually to keep it at where you want it.

Move to changing water once in 3-4 weeks

Not a fan of GFO as I'm sure it killed atleast my elegance coral and a severely impacted a couple others. personal preference... I took it out after 3 weeks.

I dont recall a fuge in your setup... consider adding one with a fast grow macro algae; at the moment I'm not having very good results with the ATS itself. so I restarted the fuge, skimmer and do a 25% water change every 3ish weeks. this has helped a LOT. however the the biggest change I noticed is when I switched from Tropic Marin Pro to IO... the corals are open much better, for now I'm going back to IO... I can get a lot more salt for the same dollars :)
 
Just turning the alk pump off for a day or two will get you back down then adjust your timing.

I have to do that with every water change, turn the alk pump off for 48hours to compensate for the higher alk in the new saltwater. Never had an issue or felt it causes any stress to just turn if off and let go down on it's own.

Funny you say that Mannish, I just switched back to IO on Sunday. I like that it TM mixes well and don't have to clean the mixing bucket so often but still hard to get over the cost. I went through 6 buckets of TM before deciding to switch back. While the tank has been as good as it every has the last few months I'm not believing it's the salt being the #1 reason. I'll know after a few boxes of IO if still looking great then it probably wasn't the salt.
 
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I'm still fighting with my tank a little bit from our honeymoon/wedding in June and feel your pain.

I'm in almost the exact same boat as you, I'm keeping a spreadsheet with all my params, and doing weekly water changes. (Changing 20 gallons on ~110 gallon system) Only real difference is that I don't use GFO.

All of the corals that were receding are now having new growth over the parts that receded. I've been focusing on heavy substrate cleaning (sand sifting) and it sounds like I've been changing a higher percentage of water every week.

(I'm religiously changing 18% a week where you are changing around 10-15% "almost every week.")

Not sure how much this helps, but I wish you luck in figuring out your problem. My plan of attack has worked out well for me thus far.
 
All of the corals that were receding are now having new growth over the parts that receded. I've been focusing on heavy substrate cleaning (sand sifting) and it sounds like I've been changing a higher percentage of water every week.

(I'm religiously changing 18% a week where you are changing around 10-15% "almost every week.")

Sorry to hear about your issue as well though very happy your plan is working for you. It's so hard to leave the tank for a while and tell yourself things will be fine then come back to a disaster.

I used to vaccuum the sand religiously during water changes but stopped that practice a month ago thinking I was doing more harm than good. I assumed the GFO would buffer against any phosphate buildup and I'm testing 0 from API test kit for nitrates. Kit is far from perfect but in the past I would at least see a color change under abnormal conditions.

My sand bed is 1 - 2 inches, I found the DSB I used to have more of a time bomb than an assist.

I did run out of Salinity and am going to use the IO I have leftover from before I switched. I'll try Taklu's idea of testing the water before and after a water change to get a better handle on any major parameter changes.
 
It's always a good idea to test a few times when doing water changes. I test my tank's current salinity. Then as I mix, I test multiple times until it's up to the salinity that I am looking for. After the salt is completely dissolved, I do another check on both my tank (for redundancy's sake) and the new water. Perform water change, test one last time.

Hopefully you can figure it out and turn things around with religious water changes!
 
When I have had problems I have done 3 or 4 50% water changes over a 7-10 day period. Might be worth a try.
 
When I have had problems I have done 3 or 4 50% water changes over a 7-10 day period. Might be worth a try.

I do this at least once a year even when things look fine. My philospophy is that doing 10-15% water changes trace elements and the like are still likely to get depleted at some point even if it takes a year or two down the road.
 
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I used to vaccuum the sand religiously during water changes but stopped that practice a month ago thinking I was doing more harm than good. I assumed the GFO would buffer against any phosphate buildup and I'm testing 0 from API test kit for nitrates. Kit is far from perfect but in the past I would at least see a color change under abnormal conditions.

My sand bed is 1 - 2 inches, I found the DSB I used to have more of a time bomb than an assist.


1-2" substrate that is larger than sugar sized your for sure doing more good by siphon than letting all the crap eventually decompose and become dissolved. I do this once a week. Having been barebottom for several years and seen all the buildup that occurs just in one week is a big eye opener as to how much gunk collects. My substate is for aethetic purposes only.
 
Tested Alk this morning and am down to 7.9. Incidently, my test kit may be off given that I did a comparison to the included checker solution and it did not come 6.7 as written on the bottle.

Phosphate tested at .17 which is interesting how much change in a matter of a few days since the last testing. I will be changing out GFO shortly and going with a larger amount to make it last longer. 3 weeks feels very short.

10% water change tonight as I'm low on salt.
 
I don't see it mentioned anywhere, so that is the only reason I ask. Temperature pretty stable? Confirm your probe isn't reading low and your tank is warmer than you think?
 
Yes, my range is under a degree variation. min. 78.5- max 79.0. Controlled by Apex. I checked it against a different thermometer a few months ago but will check again to make sure all is good.
 
Ok, strange readings. The tank tests at 7.5 dKH with the new Hanna checker. Good! I bought a 32 gallon rubbermaid Brute and more Salinity, mixed it up to 1.026 perfect.

Tested the Brute batch after 24 hours and 11.4 dKH @ 1.026! What gives? The sticker on the salt container reads 8.6 max. I was thinking it might be my refractometer but I checked and it is spot on.

I removed 5 gallons, added 5 more of RODI gave it about 20 min. and tested again. 1.022 @ 9.7 dKH. I'm not really sure what to try here but maybe this was my Alk spike problem...
 
Is your mixing tank close to the whole house air intake? That will spike the all reading everytime theres fresh air being brought in but not that much, but just a thought
 
Also the tank could read lower if all has been consumed and its not getting a lot of fresh air... This is compared to what u see in your brute can
 
The mixing tank is 2 ft. away from the air intakes but the tank is only 4ft. away, albeit higher than the mixing tank. It just seems really weird that ALK would read that much different.

At this point, do I mix it back up to 1.026 and do a water change with the high alk or do I leave it at 1.022?
 

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