Watercress refugium Experiment

[Just Toby]

[QUOTE='vspec';449880;4]I applaud your use of natural means & hope your tests are productive, however you haven't filled any blanks of your system, so its not even possible to determine if it can be prevented at the start[/QUOTE]

Can you explain a little more about what you mean as I Do not understand the question.

It is not possible to prevent nitrate building up if that is what you mean..(I appreciate that good husbandry can stop nitrate building up but i am talking about pure biomass produced by two rays) in an odd way we want to produce it as much as possible as it proves the nitrogen cycle is working.....if the watercress does not lead to a reducing nitrate though I may buy a deltic nitrate reactor and see if I can fuel it with vodka.

I could just up the auto water changes as my supply doesn't read any nitrate out of the tap but I would love to have a more natural solution. And I love he idea of the plants stripping out the nitrate.


One of my clients has a very large collection of koi and he cannot trace nitrate in the pond as he has a massive amount of cress growing in a veg filter.

 

[aquaman45]

Can you explain a little more about what you mean as I Do not understand the question.

It is not possible to prevent nitrate building up if that is what you mean..(I appreciate that good husbandry can stop nitrate building up but i am talking about pure biomass produced by two rays) in an odd way we want to produce it as much as possible as it proves the nitrogen cycle is working.....if the watercress does not lead to a reducing nitrate though I may buy a deltic nitrate reactor and see if I can fuel it with vodka.

I could just up the auto water changes as my supply doesn't read any nitrate out of the tap but I would love to have a more natural solution. And I love he idea of the plants stripping out the nitrate.


One of my clients has a very large collection of koi and he cannot trace nitrate in the pond as he has a massive amount of cress growing in a veg filter.

Good point about your clients pond Toby,its all about getting the balance right isnt it?,plants,water to fish ratio,obviously on a much smaller scale and the fact we are talking pond rather than aquarium its harder to achieve given the size of our rays and the volumes we keep them in.
Keep the experiment going,you might find you and your family will have to move out of that big house you live in to make way for the cress..LOL!!

 

[Just Toby]

I am pretty sure that the cress can do the job but I think I am going to need loads more and you hit the nail on the head that we may run out of sump space first.


The fish to water volume ration in regards to the waste is a problem, I agree. Whilst we have tanks that are large by fish keeping standards even an 8x3x3 is still just a small glass box.....especially when compared to a decent pond!

 

[Just Toby]

Last update on this thread.

The watercress must be doing something as growing very fast but it just seems to be WAY too little, Since turning off the ion exchange resin I have kept to my normal feeding and water change regimen and the Nitrates have climbed up to 75ppm over 2 weeks.

I am going back to the Ion Exchange and upping water changes.

My next plan is a Deltec Nitrate reactor as I want to get to the point where my weekly changes are purely for refresh purposes and have the nitrates fully managed.