Tank Disaster! How did this happen?

Pepsi Dave

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1 Apr 2013
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So I’ve restarted my tank after a few years with it sat in the garage since moving house.

The filter has been cycling for a few weeks, and all was good and stable! Had the ammonia and nitrite spikes and all had settled to zero apart from a few Nitrates.
I then planted a load of plants a couple of days ago, and again all was ok on water tests. A few nitrates but nothing else, all good, even as of last night.
So today on way home from work I bought some shrimp for the tank, and did another water test, and the results were way off the charts like I’ve never seen before!

4ppm+ ammonia
5ppm+ Nitrites
160ppm+ Nitrates

So I urgently carried out a 75% water change. Still had some ammonia and nitrite readings, so did another 75% water change, finally no ammonia/nitrites/nitrates. Thinking all was good to go, I acclimated the shrimp to this water and 90 minutes later once they were in the tank did another water test just purely out of curiosity.

2ppm Ammonia
2-3ppm Nitrites
80ppm Nitrates

Sadly I already know my shrimp will not last long! And more water changes now, at this time of day, will be just a waste of time, so I just want to understand why this has happened, learn from it and move on.

The only thing I can think of is that when planting I put some APF Root Tabs into the substrate.
Since then I’ve seen some of the white plastic coatings floating about. Which I wasn’t expecting because they weren’t visible at all at the time of planting.
If these are leaching into the water column is this what is likely to have caused my sudden catastrophic parameter changes? And how long can I expect this to happen?
I can’t think of anything else that would cause my water parameters to change so dramatically in such a short space of time! I’ve made newbie mistakes in the past, and never seen any results like I’ve seen tonight!

Thanks in advance.

Tank Specs:
100L Tank
No CO2
EI ferts (scaled right back for low tech and only dosed one day so far)
Moderately Planted
39W T5 on for 6 Hours
Eheim Professional 3 350 with inline heater.
Caribsea EcoComplete Substrate with APF Substrate Capsules.

Crypts (Balansae and Kasselman)
Hottonia Palustris
Limnophila Sessiliflora
Java Ferns
Amazon Swords
Bacopa Monnieri
Rotala Rotundifolia
Floating Plant (Identified as Limnobium Laevigatum - I threw the plant box/label away and forgot the name)
 
Last edited:

DutchMuch

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did another water test, and the results were way off the charts like I’ve never seen before!
yea this sometimes happens in a cycle.
Its like when the cycle is half way through usually for me.

Just my guess, im sure there is some bigger more scientific explanation to this. Maybe.

EIther way good luck ;)
 

Tim Harrison

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I guess it could be a boom bust cycle. Ecological theory has always predicted that predator-prey relationships regulate population size. For instance, the size of Daphnia populations can fluctuate massively depending on the availability of their microscopic algal prey.

In reality, many ecosystems are very stable, but an aquarium is a very artificial system and relies on external inputs to maintain balance. In the case of nitrifying bacteria, when the tank is first set up there will be a great abundance of ammonia for the colony to develop quite rapidly and levels will eventually start to drop as that "food" source is consumed.

However, if the food source is not replenished the population will crash, and in the case of a cycling aquarium levels of ammonia will start to rise again. Theoretically the decaying bacteria themselves may add to the organic load and contribute to those levels.

If another food source is added (organic waste from plants and critters) the bacterial colony may then start to rebuild and grow, but there will always be a time lag and therefore a period where ammonia levels will continue to rise before the colony reaches an equilibrium with the available food source and those levels subsequently start to fall once more.

My tanks nearly always cycle adequately enough to slowly start adding critters in around a week or so. I guess that way the filter bacteria always have access to a food source. But I usually use soil or AS which continues to give off ammonia for several months, so potentially the bacteria in my filter never experience a boom bust cycle anyway.

But the entire theory above could be a total and utter flight of fancy, so take it with a large pinch of salt. It could really just be that hobby grade test kits are notoriously inaccurate because they don't actually measure the levels of chemicals or compounds they claim to. In reality maybe the reagents are reacting to your dose of EI fertz and those released by your root tabs, or a combination of all or non of the above :D
 

dw1305

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Hi all,
I don't think all is lost, I'd carry on with a daily water change.
Moderately Planted
Could you add some floating plants? They aren't CO2 limited and this means that they can make use of the extra nutrients in the water column.

Some extra oxygen would help as well, can you angle the spray bar up? or drop the water level? or add an air stone etc.
The filter has been cycling for a few weeks
Has the tank just been growing in? or have you added ammonia?

Usually growing would be much preferred, but if you have added ammonia it may be an advantage in this case, purely because you get a different assemblage of nitrifying organisms dependent upon the ammonia loading. Usually this means that conventional cycling is entirely pointless in a planted tank, but because of your pollution event the nitrifying organism assemblage may be a "high ammonia" assemblage and able to respond more quickly.

Have a look at <"Oxygen levels required....">, it is quite a long thread but a lot of it is relevant to your issue.
The only thing I can think of is that when planting I put some APF Root Tabs into the substrate. Since then I’ve seen some of the white plastic coatings floating about. Which I wasn’t expecting because they weren’t visible at all at the time of planting. If these are leaching into the water column is this what is likely to have caused my sudden catastrophic parameter changes? And how long can I expect this to happen?
It sounds like it might be the "Root Tabs". Nutrient release in "Controlled release" fertilisers is usually controlled by the thickness of the polymer coating.

Slower release tablets just have a coating that is thicker and more impermeable, the actual nutrients are still very soluble, so if the coating is broken all the nutrients will go into solution, including any NH3 or NH4+.

Have a look at <"My unfortunate...."> , the most relevant bit is below
This really is a zombie thread, but over seven years later I think I have the answer.

I recently had to strip this tank down, because it sprung a leak, and........ .....when I started scooping the sand out I found a number of empty little orange "controlled release" fertiliser prills, and there used to be a jar of these in the kitchen (for the house plants).

ymer-Coated-Controlled-Release-Fertilizer-10-10-15.jpg


I've definitely never added them to the tank, so I assume they were the cause of the incidents in 2010.
Cheers Darrel
 
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Personally, I think upon starting up the tank you had a large heterotrophic bacteria colony due to high organic levels and subsequent lower oxygen levels, the heterotrophs being happy bunnies, keeping the levels in check. As they "ate up" the carbon, they crashed and the nitrifiers are still not up to scratch.

I'd do large daily water changes, increase surface movement for aeration and hope the long term microbial community establishes in due time.

Alternatively feed the heterotrophs again with a spoon of sugar granules, no joke ;), that's providing my theory is correct.
 

Pepsi Dave

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1 Apr 2013
Messages
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Thanks for the responses, I'm still not sure what caused my problems, but due to how quickly things went off the scale, and even with full water changes, to see things bounce right off the needle within literally 90 minutes, I'm putting it down to the substrate capsules.

I was doing daily water changes - 100-150% daily for a week until things settled down. Lost the vast majority of my shrimp, and had a few more die since. A colony of 25 shrimp is now down to about 7!

Since things stabilised, I started to notice a small amount of ammonia in my test readings, which I've put down to a dirty filter. Considering there are no fish in this tank, the amount of "crap" that came off my filter media was disgusting haha! So hopefully all my troubles are behind me. Lesson learnt with potent substrate capsules, I also think I used way too many as well, which ain't smart.

@dw1305 Thanks for your input Darrel, I've been doing a bit of reading about your "Duckweed Index" and have now also got some floating plants to help with excess nutrients etc.
On the Duckweed Index, is there anything that you can point me in the direction of that illustrates what my floating plants would look like with various deficiencies?
I was lean dosing EI to begin with, but started to notice my submerged plants struggling a little bit, especially with new growth being yellowish and a bit stunted. From here, I started to up the EI dosing and added floaters to aid with any excess. Last nights water test showed almost no nitrates so in that respect I don't *think* I'm dosing too much, but equally, I'm not sure if I'm dosing too little.
Other than yellowing of the leaves on the floaters, in which case I've added ferts, I'm not sure how to identify other deficiencies so that I can adjust my EI recipe accordingly. Notwithstanding that I'd also like to understand why adding a particular element will make a difference etc, rather than just upping the dose.
 

dw1305

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Hi all,
On the Duckweed Index, is there anything that you can point me in the direction of that illustrates what my floating plants would look like with various deficiencies?
I don't have specific pictures that relate growth to each individual nutrient. Usually I just add a complete fertiliser mix when plant growth has slowed unacceptably.

The exception to that is the "easy to pick out" iron (Fe) deficiency. This is what iron deficiency looks like (look at the colour of the younger leaves) (from @jameson_uk's <"Duckweed Index say.....">).

dad12186cb152cccee11028dc11c34f4.jpg


I've started more regularly dosing iron (as FeEDTA) and magnesium (as Epsom Salts), purely because you only need to add a small amount (of either) to get a growth response, if they are lacking. Also if you wait until your plants are definitely iron deficient, it takes a while for them to recover.

All the other "deficient" nutrients cause small plants where the older leaves are yellow (the elements are mobile within the plant) and you get a pretty rapid greening when you add the deficient nutrient. Have a look at <"which NO3......."> and <"Dosing for a Barr non CO2">.

Looking back at my Limnobium scan (from "Dosing for a Barr....", the thread is from 2011) I can see that the central plant is also iron deficient (pale new leaf). I think the larger plant (bottom left) would have benefited from some magnesium (Mg), but that would be more of a guess.

limnobium-jpg.jpg


Because of plants growth requirements the most likely (to be lacking) nutrients are nitrogen (N) and/or potassium (K), followed by phosphorus (P) and then magnesium (Mg). Plants need all fourteen essential elements for growth, just in amounts <"that differ by several orders of magnitude">.

This is some really healthy Frogbit (from <"an iwagumi called...").

sigrjybcq-width-3264-height-2448-cropmode-none-jpg.jpg


cheers Darrel
 

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