Slow Tank Crashes. Symptoms corrective measures and outcomes.

[maroun.c]

We see a lot of threads talking about tanks starting to fail over time. Many relate it to Old Tank Syndrome but in reality something is going wrong and reefers got to pinpoint it and correct it.
Many times reefers come up with 1000 corrective measures that most of the time end up speeding the crash or sometimes reverting things withuot knowing the real cause.
Lets post those frustrations we're usually not proud to talk about and list the Symptoms, Tests, Actions and outcomes.
In my case I upgraded from a 150G which started to fail just before the move (non detected High litrate level due to a faulty testkit) to a 400G Display tank and total system volume of around 500 Gallons up to 750 G currently. For some reason the system kept failing to kick start. Continued to have severe Algae Cycles with some Cyano blooms on the sand bed which wouldn’t go away with increased flow, increased skimming and manual removal for months.
Any SPS coral I added would loose polyp extension, and start to dry up and loose tissue within 10 days max, few would STN or RTN. Some LPS did fine and I did lose a few others like CandyCances, Chalices, Scroll Corals, Pagoda, … weirdly 3 SPS corals which were reduced to a few brown polyps (Spongoides, Pink Pocci and Stylo)survived the now 3 years Dilemma.
Sent water for professional lab testing for Chloramines and it verified my RODI was able to deal with the within limit amounts I was getting from Tap water. Also tested for Alk Ca and MG and it matched my Salifert testing. Cross checked my slaifert testing for PO4 and No3 with Deltec and Rowa and API tests and it was the same except for Phosphates at 0.08 instead of the 0 I was getting on Salifert. Didn’t give it much thought as I thought the excessive water changes I was doing would handle it and I tested my fresh mixed freshwater and it came out with a 0. the alga I was getting disappeared at the 1 year mark roughly so I thought that Nitrate and phosphate issues were excluded.
Made the following changes/trials:
-Tried Biopellets for some time with a clear effect on skimming performance but no effect on coral losses.
-Periods with Heavy consecutive water changes like 2-3 100Gallons changes in a week followed by 75 G changes weekly for 2-3 months and no improvement. Thought I had some accumulation of something in the water and that this would offset it.
-Periods with no water changes thinking new water just in case the new mixed water was contributing to something.
- Color changing heavy metal removing media with no change in color.
-4 months cycle with the following Zeo additives: Zeobac, Coral Snow, Zeo Start 3, and Zeozyme which was very expensive considering the system volume and only helped with the Cyano which disappeared but corals were still drying up in less than the 10 days mark.
-around 7-8 months ago my Nitrates was testing between 5-10 and it was the only thing I could pinpoint so I removed my PO4 media thinking my PO4 at 0 was limiting nitrate reduction.
-My Display is lit with MH and T5s so no LED related cause. also the Frag tanks connected to the system were showing the same issue and they are lit with LED and T5 so it was clearly a water quality issue.
2 months ago while testing water with a friend we used his Hanna Phosphate test to check my phosphate and it came out at 0.9. Following morning sent water to Lab testing and came out at 0.81. pulled out a Hanna test that I had purchased a year ago and still not used and it tested at 0.89.
At this stage I wasn’t sure if that was my only issue, and it was weird how levels climbed that high with 2 different Salifert testkits and API and Rowa testing much lower. The system did run for months with an underrated skimmer and a period with lower flow, I had used Ceramic rocks yet logically whatever amount of Phosphate should have been dealt with by the excessive water changes I was making.
Since then I have changed around 700G and used up around 2KG of Rowaphos.
this led to my nitrates dropping to 0 so I stopped the water changes and relying now on Rowaphos to deal with the phosphates. The first Kg dropped the level from 0.8 to 0.3 but since then the drop is very slow (presumably due to rocks and sand leaching) and I'm currently at 0.10.
Weirdly the remaining frags colored up at 0.3 and started showing early signs of growth.
Still have a long way to go to bring the levels below 0.03 and it did cost me a 5 years collection of Corals I gathered during extensive travel but finally on the bright side I know at least what the cause is and I'm correcting it.
Do share your stories and hopefully what you pinpointed as reason and the changes and outcome you got.
#reefsquad

 

[brandon429]

I have beaten OTS, it cannot occur in my tank

6 inch dsb

 

[brandon429]

how I got there, even with a DSB that is championed to be the cause of OTS

-most tanks have feed input daily and it rots in the tank, so it casts its waste (P etc) into the substrata to be regurgitated later, the current school of thought holds
my tank does not do this. I have stocked with animals that are ok with weak mid week feedings or none, and then a huge giant blast feeding just before a larger than normal water change. I altered what breaks down in my tiny system

-water change percentage

mine can't be beaten period.

-bed input vs output

OTS hallmark is eutrophic conditions when the diaper overflows, mine doesnt fill.

All my whole waste particles are in the top two inches of my sanded, not the bottom two, because of the way my system is ran vs typical systems that are forever inputting and never outputting.

I blast clean my sandbed annually in those top layers anticipating what happens if you dont

in short, anyone who replaces their sandbed before it regurgitates has effectively stopped ots -as long as- a phosphate uptake method, or prevention method, was deployed to lessen or make normal substrate inclusion of phosphates. I do not believe you have to bind them, my tank uses no GFO it just does big mean water changes right after feeding time.

Im not claiming what I do is practical for larger tanks, just that I am certain no OTS will ever occur in my tank. You wont be able to look at any of my aquariums at any year and deem them eutrophic. they will look oligotrophic even if the phosphates are off the charts, which I think preventative maintenance w prevent heh

 

[brandon429]

Pauls 40 year old tank is similar in planning

he has a reverse ugf to handle the incursion/excursion balances

he does big maintenance at times, to remove what others continually let compile. all the oldest tanks from any size genre do similar things. the tanks that crashed didnt, they followed the norm. this is my sandbed its almost 10 yrs and has never been removed

look at that nitrification nom nom nom

 

[Shep]

Tagging along!

 

[maroun.c]

What we're looking for is any info about tanks that went bad, dosen't need to relate to old tank Syndrome. or in other words crashes or tanks that started to go downhill without an instant failure...

 

[Nishant]

In my case, I am curious to know whether gradual rise in level of nitrates while efforts are being made to counter them (with temporary, intermittent success) can also lead to slow tank crash ?

The corals (SPS, LPS and soft leathers) are all growing fine and T5 lights are working great. Frags are also growing well.