My 765 gal tank...Part 1...

Hi to everyone…before I start writing about my tank I just want to say that I don’t speak or write perfect English... so I apologize if you see bad spelling….…

I want to start this article saying that for me was a marathon to make this tank work, it took me more than one year to finish it because I didn’t have any experience at all on big tanks and big filters….I am not a construction engineer or a construction worker and everything was new and difficult for me, I had to search and research a lot and I had to deal with a lot of problems with unexperienced workers on aquariums. Its not that they don’t know how to do it… its just that its not common to build a big tank ….it’s a lot of water…so everything has to be perfect…..



Anyway…we had to think a lot to fix mistakes……..but I learn a lot in the process. I really recommend to all monsterfishkeepers that want a big tank, to take advice and supervision of an experienced person “on big tanks”…be practical if you have the money……unless of course you are a creative person with the soul of an inventor that likes getting into trouble and into everything and make your life a little miserable in the process….hey I am sure you like getting into problems if you don’t… you weren’t here reading this article…and keeping big fish…



This article its going to be a little different because I don’t have pictures of the construction process like the other ones but I want to share a lot of images of the tank completed and explain the details of the installation and how I designed it …. I hope its going to be useful and exciting to read…

The tank is made of plywood and fiberglass, and the process of fabrication was the same as other plywood tanks shown in other articles… using plywood, fiberglass and epoxy paint… I choose plywood with fiberglass for security reasons, also because its cheaper…and because I live on a 16th floor …so we had to split the tank on 2 pieces to bring it home…. we got each piece into the elevator and then rejoin the pieces with fiberglass. There was no way to bring a complete acrylic or glass sheet into the elevator…that’s another reason I choose plywood…

The size of the tank is 3.40m x 1.20m x 75cm (around 765 gallons) it has 5 windows… as you can see the tank its beside the concrete column on the joist of the building…



The tank is on an iron structure with iron doors also made in 2 pieces, each piece of iron that contacts the floor have a big screw so we could level and balance the tank, because the floor its nor perfectly flat so the water level gets balanced…





We used a silicon sealent from the brand syka called sykaflex 15lm to put the windows on place….. the products of this brand are known for sealing boats and that kind of stuff, anything underwater pressure…


FILTRATION:



We made a fiberglass sump with 10 chambers for biological and mechanical filtration…the size of the sump is 2m long x 80cm wide x 50 cm tall (around 200 gallons)…the water flows a little different from other sumps…in this case the water flows up and down like all sumps but also from left to right and right to left…that is the order of chambers…











First we drilled 7 holes at the bottom of the tank to put 7 bulkheads of 1.5 inches for proper filtration, my idea since the beginning was to use 3 of those bulkheads as drains to take the water to the sump…two of those bulkheads are situated on the center on each side of the tank and the other on the center of the back part of the tank… the other 4 bulkheads work as returns to the tank on each corner…





I didn’t want to use the typical installation that use stand pipes or a hole on the top of the tank to take the water to the sump because in this case only the water on the top of the tank goes to the sump and I wanted that the input bulkheads works as pool drains and most of the dirt that are on the bottom of the tank gets to the sump by gravity…so I can siphon the tank less often….



The problem and the question was this…how I am going to stop the water of the sump to overflow in case of no electric power? The last thing I want to see is all the water on the floor destroying the roof of my neighbour….. People use stand pipes to prevent this because when the level of the tank gets under the level of the stand pipe the water don’t go to the sump…but how I am going to do it if I don’t want the stand pipes?

The solution was to install 6 (1 inch) floating valves (ballcock)… two valves for one bulkhead drain…we had to think a lot to install this valves and how to position them so they can work ….we made a lot of tests to make sure all the 6 valves open and close automatic at the right moment at the right level at the same time….it was difficult to achieve this because there was not enough space for the floating balls to open or close so we had to cut each stick of the floating balls at the exact size….and fold some sticks….







I connect hosepipes in each valve and place them in the right chamber so the water gets well filtrated…also the hosepipes help to avoid the noise of the waterfall….

I put volcanic gravel in the first 8 chambers for biological filtration, the last two are empty because there is the inlet bulkhead to the pump…as you can see…









For mechanical filtration I bought some rectangular plastics with holes at wall mart and put them together with plastic belts to cover each chamber …





I put the filter material on the plastics not too tight so the water can flow normally,
after this I attached with plastic belts another plastic to the rectangular ones to prevent the filter material to float with the water.











After the sump… the water goes to the pump, then the pump gets the water to A jacuzzi filters that stops 3 micron solids if I remember correctly to keep the water crystal clear. Then the water goes to five returns, four of the returns goes to the tank and the one left goes to the first chamber of the sump…. why?









Well I had to balance the amount of water that goes to the sump and the amount of water that goes to the tank, so if the pump takes more water to the tank (more than the water that falls to the sump by gravity) then the last chamber of the sump gets empty and the pump suck air and no water. So the return that takes the water from the pump to the sump is key because it prevents that the sump gets empty, this return have a valve (the key valve I call it) so I can regulate how much water goes to the tank and how much water goes to the sump… but if you think about it… its not an easy task… this valve have to be almost closed so there is lees water in the sump… as a result the floating valves are almost full open because the surface of the water is in the middle of the sump…if the floating valves are half open then there is no purpose of the filter because this means that only half of the water of the tank goes to the sump…and also this means that the pressure of water to the drains is less…and consequently less dirtiness falls to the sump…

If I open the key valve completely what happen is that the water of the sump wont go to the tank and keeps recirculating in the sump….also what happen is that the water from the tank falls to the sump by gravity and then the floating valves get closed little by little until no water falls to the sump. On the other hand If I close the key valve completely what happen is that the pump carries more water to the tank than the water that fall to the sump by gravity … the pump suck air and no water….

So everything has to be balanced …(if I change the pump to more horse power then the design doesn’t work…or if I use only 2 drains then again the design doesn’t work, and if I use too many drains then the floating valves will not be completely open all the time because the water that falls to the sump it’s a lot more than the water that goes to the tank…. in this case the pump needs more power…so everything has to be balanced.

The floating valves prevents the water of the sump to overflow but also stabilize the level of water in the sump with the key valve that keeps enough water in the sump.

But that’s not it, the other four returns carry the water to the tank …. I had to put reductions on each one of the returns…the reductions also prevents the last chamber of the sump from emptying because if I don’t use the reductions then more water (more that it should) goes to the tank and again the pump can suck air. But the reductions also help to create a nice water flow on the tank….each one of the four returns also have its own valve and I can control the amount of water just like in a jaccuzi. Also I put check valves on the returns to prevent water to go from the returns to the sump In case of no electric power.







So as you can see everything has to be perfectly balanced because it is an open filter and the way I did it using the floating valves. You have to calculate everything …the size of the bulkheads, how much water falls to the sump by gravity depending on the amount of water (if the tank its not full of water then the quantity of water that falls to the sump by gravity is less because its less water weight and pressure)… also you have to calculate the size of the pipes, and also the size of the sump, the power of the pump (I use 1/2 horse power pump), the size of the returns and everything. Why? Because it is an open filter and I am not using stand pipes…I am using drains on the bottom of the tank…. if you have a closed filter then you don’t have any problems because there is no risk…all the pools have closed filters but the water of the pools don’t have the waste of the fish and the food… if I have used a pool filter I am pretty sure I had to clean it every 2 days…..I could use a pool filter but a really big one and I really don’t have the space. Everything that I did worth it because I change the filter material of the sump every month and if I want I can change it every two months… I mean after a month there is no evidence of the waste blocking the filter….but the most important thing…. Is that I have a big biological filter and its basic for a fish tank, and I can tell you I give my fish a lot to eat.

Now I know why hydraulic engineers exist, I can tell you in my experience that most of the pool plumbers don’t know how to calculate watercourse and pressure and how much water is running on the pipes per minute depending on every situation… size of tank, size of pipes, size of pump, gravity etc, etc, etc why? Because they don’t have to… they work with closed filters…

NOISE REDUCTION:

Well…. after everything was working I realize I couldn’t stand the noise of the pump I just couldn’t… I mean this is not a powerhead it’s a pool pump (and the guy who sold it to me told me that it was the most quiet of all pool pumps) …I prefer not to have a tank if I have to listen all day to that noise…or only 5 minutes…

So I had to do something … I have some experience on noise reduction and I know noise its like water… it can escape from a tiny little hole, so I came up with the idea of using
doors like recording studios use, made of a solid material using the rubber sealant material that refrigerators have…because it is an iron structure that supports the tank… the rubber with magnet seal to the iron… just like a refrigerator. So I called a carpenter and we did a solid 1.8cm MDF wood doors with the rubber material and everything worked perfectly… the noise reduction was 95% …my refrigerator make more noise…..we not only made the doors but also the wood structure that holds the wood doors…the wood structure also seal the bottom space of the iron structure between the carpet and the iron where the level screws are and also the back part of the tank …essentially we made a wood furniture around the iron structure for noise reduction and better look…





















The next problem was this… the seal was so perfect that there was no ventilation at all… the heat of the pump was making the water of the sump warmer so…..at this moment I was very frustrated and I had to have an idea…I came with something and I had to sacrifice a little noise reduction for ventilation….

VENTILATION:

I use the back part of the tank for ventilation, the little wood doors for noise reduction at the back part of the tank were useless…. I bought a little fan and a medium special extractor that can be all day working, we made two 4 inch holes in each side, we put in one of the holes the little fan and in the other an aluminum duct which connects to the extractor that is exactly besides the pump…. so all the warm air that the pump creates the extractor takes it out… and the fan gets inside fresh air …after all this I realize I don’t need heaters for my tank…. the temperature is 24°C sometimes a little more.













The real limitation on a big aquarium (I am talking about a really big aquarium ---10,000 gal or more) is the space, I am not talking about the space for the tank …I am talking about the space you need for everything else, if you have the space for a pool aquarium you also need a space for a big machine room and filter… and also if the tap water is not optimal you also need a tank for condition at least half of the water that your tank holds if you want to change the water fast…. also a good pipes and valves installation… the ideal is to have a separate room for the filter and the pump….and keep it far away your bedroom and house so you don’t have to deal with all this noise problems. Normally the machine room on pools are underground….if you want not to listen to any of the noises of the pump or pumps …you need a machine room far away…if you have a machine room near you bedroom or house this will help to reduce the noise of the high frequencies but not to the low ones… but that is enough for most of the people…but if you want to get rid of the low and high frequencies then the pump most be underground and far away.

So if some day I have the space, the money and the long term desire and commitment to have a pool aquarium… I will be thinking on a machine room underground and far away. (Not any time soon of course...).

LIGHTS AND LIDS:

I use plastic lids and wood lids, the plastic lids helps to prevent evaporation, also when I feed the fish with floating sticks some of them splash the water and if I only use the wood lids the water goes out form the edges, also the plastic lids protect the cables and connectors of the lights from water…I had to use connectors inside the wood lids because there are 3 wood lids, and I have to join and connect them all to turn on the lights…all the cables are hidden.







The purpose of the wood lids is to support the lights and cables (the lights are T5 fluorescent and the plastic box of the lights are made for bathrooms and are perfect sealed to prevent humidity entering the bulbs and cables) …., another purpose is to prevent that a big fish jump out of the tank, and to prevent people to throw things into the tank. The wood and plastic lids have little lids to feed the fish…The last wood and plastic big lids have a hole near the window so the tank keeps ventilated, also all the hosepipes of the air pump for bubbles enter from this back side of the tank, and also the cables of other fountain pumps that I use in case the filter its not working and to keep more water movement on the surface.














WATER CHANGE:

To drain the tank I use a flexible hosepipe of 1.5 inches that I connect to one of the pipes that is connected to the drains of the tank, in the middle there is a valve, so the tank gets empty by gravity really fast…the flexible hosepipe goes directly to the drain of the bathroom.







To fill the tank with water I use my oldest tanks to prepare the water (1-150 gal, 2-60 gal and four plastic boxes of 40 gal each, I don’t use any conditioner I only keep the water moving with little pumps to eliminate chlorine and of course I add salt…after that I use a bigger summersible fountain pump that takes the water to the tank with a normal hose pipe….I change only half of the water.

DECORATION AND FISH

For decoration I use granite rock (river rock its called in Mexico), plastic plants and flowerpots (caves for some fish)…



I keep midas cichlids (I have them since they were born) In this tank they have fry every month…the parents take care of them but at the end if I don’t take the fry out some big fish eat them or they gets to the drains and then to the sump…



I keep also Giant gouramis and Pacus, I took the big ones from a restaurant (all this big fish were miserable… they were on different tanks but they couldn’t turn around or swim…they were in a box) …the guy of the restaurant told me that the big ones are 12 years old…but I don’t know….they are 24 inches long and I know its better to have a pool for them…but they are now way better than before…they swim a lot and pursuing each other…sometimes they get very aggressive…they have teeth….

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CONCLUSION: (Some thoughts)

For me the goal of keeping fish is to really enjoy it… I like to sit one afternoon on the couch and see the fish swimming and watch the bubbles of the water…. I am not a guy who enjoys cleaning the tank every 4 days and I don’t think anyone does…so that is why If you are going to build a big tank then please think again….because you have to make it perfect…the goal of keeping fish is to have a moment in peace and go to another world…not to have problems and dealing with more problems everyday….so I can tell you that before this tank I wasn’t enjoying anything about fish keeping because my old tank setup was not in perfect condition…I had a lot of leaks on several times, the water wasn’t clean , I had to clean the tank pretty often and I didn’t have the time to do it…some days I just woke up and think ¿Why I am keeping fish? I have other things to do…….But I was so obsessed to do it right that I finally did it…and now yes I can tell that I am enjoying it.

So remember…if keeping fish is not letting you to have a normal life, if you are using more time than you should then don’t do it…because you can get a little crazy and frustrated like I was..….but if you are going to do it then you have to do it perfect and spend enough to keep everything smooth and really enjoy it in the end…and of course your family should agreed on it if you know what I mean and because if you are not in town then who is going to take care of the big fish? ¿Do you really have the time and budget to do it? You can have a budget but maybe you are going to spend more because in the process you can see that something is missing here and there…….unless you have some experience. Thinking big its good but if there is a problem…then it’s a big problem… there is no room for mistakes….one mistake its equal to wasting a lot of time and a lot of work …the upside of all this is that you will learn a lot in the process…

It seems in my conclusion that I am trying to discourage everyone to build a big tank…but I am not.....I am just trying to say that you need commitment and responsibility, and if you don’t have the experience on big tanks then you should know that its not going to be easy at the beginning…and you will have to dedicate time to study everything like I did...…

Anyway......I hope all monsterfishkeepers enjoy my article and if anyone have a question I will be glad to answer it…but I am a very busy guy.. so Im sorry if I don’t respond immediately….I will try…...