A ~19,000 Gallon Fish Tank

nahham

Member
Originally Posted by Beth
http:///forum/post/3217512
I would maybe ask Bang Guy about a DSB with the set up you're planning. Not sure it would be a good idea for this setup. DSB are dependent upon sandbed detritivores to operate well, and I'm not sure how practical that would be with what you are planning.
A viable DSB should be 5-6" deep at least.
5 - 6" isn't a problem. :) Will look up Bang Guy, thanks.
 

bang guy

Moderator
This is quite a project.
I have a few questions about the water.
How turbid is the water where you will be gathering it?
After dark is there a mass of zooplankton coming up from deeper water?
What types of algae can be found nearby in shallow water?
My instincts tell me that a DSB isn't going to be viable long term and I don't believe you have any need for it. I would recommend just enough sand for aesthetic appeal and no more.
I'm not sure what the refugium will help you with. What are the goals you have for the refugium?
I don't think you will have much luck making the water clear without some type of mechanical filtration.
 

nahham

Member
Originally Posted by Bang Guy
http:///forum/post/3218440
This is quite a project.
I have a few questions about the water.
How turbid is the water where you will be gathering it?
It is clear most days. Sometimes it's greenish which is good right? I am also getting the water 2 - 3 meters below the surface.
After dark is there a mass of zooplankton coming up from deeper water?
I have no idea how to tell, but there are always small/bait fish swimming around where I get the water from, even at night. The people from the ministry of environment and water also mentioned this and suggested I point a light at sunset to help collect some. The water in front of us is quite deep (6 - 8 meters).
What types of algae can be found nearby in shallow water?
We only get real algae outbreaks in summer. Currently there are none I can see, and I wouldn't know what kind :). How can this be an advantage/disadvantage?
My instincts tell me that a DSB isn't going to be viable long term and I don't believe you have any need for it. I would recommend just enough sand for aesthetic appeal and no more.
Can you please explain more?
I'm not sure what the refugium will help you with. What are the goals you have for the refugium?
First and foremost, a place to expand and install mechanical equipment if need be. Second, I am planning to get most of the water from the sea but there are sometimes where it is not viable (having red tide for instance) and I would like to be able to circulate the water within the tank and a refugium would help with the nitrates, wouldn't it? Third, I read that having a refugium will help with the reduction of hair algae in the main tank. Fourth, I've read it is a good place to grow food: copepods and others. Finally, I was hoping it would help in the water quality but it seems you believe it will not.
BTW, thank you very much for taking the time to answer some of my questions.
 

bang guy

Moderator
Ahhh, red tide.
OK, I need to take time to think about what happens when you must recycle the water in the system for extended periods.
Does this ever last more than 2 weeks?
 

nahham

Member
I think it definitely lasts for more than 2 weeks. I'll have to confirm it with the ministry of environment and water though.
 

bang guy

Moderator
OK. Then it's going to need to ability to be self contained. That makes a significant difference in planning. It also make the refugium a necessity in my opinion.
For waterflow I'm thinking you should use one of your pump just for circulation and use the other to being in fresh sea water like you planned. Is there a way you can set it up to bring in sea water every other hour? Is it hard on your pump to start up frequently? Nothing wrong with running continuously but it's overkill and you could save some electricity.
 

nahham

Member
Originally Posted by Bang Guy
http:///forum/post/3218930
Is there a way you can set it up to bring in sea water every other hour?
That isn't a problem, the people that sold me the pumps has a high-end timer system that I had my eye on.
Is it hard on your pump to start up frequently? Nothing wrong with running continuously but it's overkill and you could save some electricity.
I think it will be better to have it start every other hour.
This raises a couple of questions: [list type=decimal][*]Should the pump that brings in fresh water from the sea pump directly into the display, or should it go through the refugium? I am leaning towards the fuge but I wanted to know what you thought?
Would it be a problem if the pump just pumped into the tank through one place? I currently have 4" pipes and its such a pain to work with them. I'm then planning to have submersible pumps that take care of the flow rate? (thanks bms for the info)
[/list type=decimal]
Thanks..
 

bang guy

Moderator
1 - I recommend pumping the new seawater into whichever container will have the highest water level. If the water level will be the same then I suggest not pumping new water into the same container that overflow the water back into the sea. Other than that I do not see a significant difference.
2 - Pumping into a single place is fine.
I recommend for something this large that you attempt to situate the waterflow so that it causes a circular waterflow pattern in each of the containers.
 

nahham

Member
Originally Posted by Bang Guy
http:///forum/post/3219123
1 - I recommend pumping the new seawater into whichever container will have the highest water level. If the water level will be the same then I suggest not pumping new water into the same container that overflow the water back into the sea. Other than that I do not see a significant difference.
2 - Pumping into a single place is fine.
I recommend for something this large that you attempt to situate the waterflow so that it causes a circular waterflow pattern in each of the containers.
Thank you very much for this. :)
 

nahham

Member
OK a couple of updates for all of you.
The v2 of the plumbing plans are illustrated here:

A redundant system with 2 pumps and a couple T connections that connect the pipes coming from the sea and the fish farm to the pump. The refugium looks so small in this illustration, maybe I should enlarge it a bit (everything is to scale). If I have my way, the whole backyard will be filled with aquariums and related stuff. :)
That's that for the refugium.
As for the aquarium itself. The workers will start to plaster the walls today (it is 1:30am Monday here). I am planning to go with epoxy for paint just because most of the walls will be covered with rock and the concrete is marine-grade. After the plastering and paint is done, we will do a leak test as the workers will start to work on the fish farm and the refugium. I hope nothing leaks or it will really really suck :).
 

nahham

Member
Originally Posted by Bang Guy
http:///forum/post/3220242
Tell me what happens for waterflow when Red Tide hits.
I am not sure if I understood what you are asking but here goes..
Normally, when the water is good enough, the waterflow will be as such: sea --> refugium --> aquarium --> fish farm --> sea. It will be an open system to a large extent. The feedback from the fish farm to the refugium won't be used in a normal situation.
However, when there is a need to close off the sea supply, here is how it is done:

Does this make sense?
 

bang guy

Moderator
Originally Posted by nahham
http:///forum/post/3220736
Does this make sense?
Yes! I understand very well now.
You will need to eat a lot of the fish in the farm when red tide hits. The bioload may overwhelm the refugium depending on how many fish are in the farm. I'm not experienced with this type of aquaculture though....
 

nahham

Member
Originally Posted by Bang Guy
http:///forum/post/3220748
Yes! I understand very well now.
You will need to eat a lot of the fish in the farm when red tide hits. The bioload may overwhelm the refugium depending on how many fish are in the farm. I'm not experienced with this type of aquaculture though....
Well the fish farm wasn't overloaded at all. The highest number of fish we had was 300, averaging 200 in a 45,000 gallon tank :)
 

bang guy

Moderator
Originally Posted by nahham
http:///forum/post/3221797
Well the fish farm wasn't overloaded at all. The highest number of fish we had was 300, averaging 200 in a 45,000 gallon tank :)
Oh, OK, I had the wrong impression. I think you have it under control.
Looks exciting
 

nahham

Member
I'm currently travelling and don't have any photo updates. However, since I don't have any actual photos to show you. I can share some designs we have for the aquarium. Here is the seating area design:

Keep in mind that the area facing the seating area is around 11m (~36ft) wide.
Any ideas?
 
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