exam question for the 'I am the plant setup genius"

[HugoFishes]

How many java fern is needed to reduce nitrates level to 0 in the following situation:

225g tank with a 55g sump.
Stock list around 12 large fishes. All with the potential of exceeding 12" in length.

Assume that the tank is fully cycled and the stock is overly fed 2 times a day. Nitrites and Ammonia is at 0 even with water change of 25% every 3 weeks.

A) 5 Java fern
B) 10 Java fern
C) 15 Java fern
D) 20 Java fern
E) I have no bloody idea

Question from my local college marine and freshwater biology professor.

 

[jcardona1]

how can you even answer this?

 

[oOMO3NOo]

i dont think there is a way to answer unless you find out how much nitrates the fish and food is producing and how much the plants take up and that will depend on the size of the plant. and what the nitrates are at to begin with. so this question seems impossible to answer without more info.

 

[Knowdafish]

0 ! Just don't feed the fish!

Seriously, there are way too may variables to come up with an accurate answer to your question.

 

[dzb912]

i have no clue

 

[Frostyone]

How large are the fish?
How much waste are they producing?
How much nitrite/nitrate/ammonia is the fish/food waste/filtration producing?
How much bio capacity in the filtration?
How much lighting is the tank under? (total lumens and spectrum)
How long of a photo period?
How fast are the plants growing?

All of these questions and many more would be needed to be answered first before you could even get a ballpark estimate.

 

[cassharper]

I would go with e because this is unsolvable with the information available.

 

[WyldFya]

As stated there are many factors that aren't given. Especially with java ferns this is difficult. Co2 is one major component, as is lighting, fish waste levels, and most importantly the size of the initial java fern plants.

 

[frasertheking]

if you had the fish in the 55 and the larger tank full with java ferns in optinum condition it might be possible with minimun feeding but they are slow growers

 

[movitt]

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