250G High Tech Tank

[Consigliere]

There have been several mentions of a future, big tank in some of my posts.  My 70G tank was actually re-setup to be a proving/testing ground for learning to run a higher tech tank so this big tank would not start out as a huge disaster.  Well, the time has finally arrived to start this project.  I received a call today from the tank builder, Bow Valley Aquarium in Calgary, Alberta, Canada, that my tank has been built and will ship to me on Monday.  All I can say is finally!  The builder selection is a long story, and if you ever want my opinion please send me an email.

Although I haven't actually received the tank yet, I have a few things that I am going to post before the big arrival.  I've got a drawing of the tank back that I supplied to the builder.



The overall tank dimensions are 66" long x 26" wide x 36" tall.  The tank will be 3/4" Starphire glass on the front and sides with a rimless eurobracing design.  Clear silicone will be used for the joints and the background will be a navy blue laminated sheet.  As you can see the tank has been drilled with five 2 3/8" drilled holes for water flow.  The top two holes are for water return to the tank and the bottom three will be for overflows.  The plan is to plumb the tank for silence using a U style overflow and a DIY custom spray bar for the returns.

I have been finishing my basement for a while and this aquarium will eventually be the center piece.   I have put in some hardware already that I will post prior to the tanks arrival.  The process so far has been a few months, but I will compress this into 1 or 2 posts.  Hopefully, by then, the tank will have arrived and the real action will begin.  I'm going to build a custom stand for it.  I'm hoping to finish up with a fully automated tank with a foolproof, fail-safe design.  I'm sure there will be a few mishaps as things get worked out.  Just hopefully none while I am asleep.

Anyone with any experience moving large glass tanks like this?  I was thinking of calling a moving company to do it since I figure it will be over 500lbs.

[Snider82]

I'm very excited to see the progress of this build!!  take 1,000,000 photo's along the way!

[OttawaFolkFestivum]

Looking forward to seeing the progress. Sweet tank!

[Consigliere]

There will be plenty of pics, don't worry about that!  I actually have a ton already of some of the stuff I have been working on for the tank.  I'm going to be posting a DIY exhaust system soon.

[sdivell]

Great!  When does the tank arrive?

I suggest movers with insurance.  Worst thing that could happen is you get some people to help you and you break it and nothing to cover you for your loss.

I volunteer to come watch you move it though 

[salvini55]

Sounds sick... Exhaust sparks my interest! any chance of a DIY turbo as well  . I suggest 25+ lbs boost min. for sure!

[Consigliere]

One of the things I am concious of with keeping tanks is the humidity they create.  I have never experienced a tank as large as a 250G so I can only imagine the humidity it will create.  I am trying to address this by exhausting the hood section of the tank out of the vicinity of the aquarium.  Here I will have some photos and explanation of how I created an exhaust system in my unfinished basement that will allow me to exhaust the hot, humid tank air to 1) my furnace cold air return during the winter (improves heating efficiency and will help humidify the house during the super dry Canadian winters) or 2) outside using my dryer vent during the summer.

This system was put in months ago, before I started finishing my basement.  To start, I had to put together the piece which will actually sit inside the hood and draw air.  I am using a 120V 4" drive exhaust fan that was given to me as the first piece of hardware that will move air.  I attached it to a 4" PVC elbow using some nails and construction adhesive.  Once the adhesive dried, I wrapped it in duct tape to make the seal air tight.





The next step was to mount the assembly to a floor joist and add an electrical junction to house the electrical connections for the exhaust fan and the flow boosting fan (to come).  I drilled a couple holes into the PVC elbow and screwed it to a floor joist and mounted a standard light junction to the joist so that the junction was flush to the PVC elbow.  This will give me access to the junction in the future since it will be below the ceiling drywall.




In all honesty, at this point I figured I just hook up some more PVC, and the drive exhaust fan would be able to overcome the head pressure and move the air from the one end of the system to the other.  Boy was I wrong.  I had no flow, so I had to figure out a good way to boost the pressure.  Walking through Princess Auto I noticed furnace duct boosting fans.  What do you know, they had a 120V 4" fan.  Perfect!  So I mounted the fan at the elbow and wired it up to a 120V electrical cord.  In hindsight, I should've placed the boosting fan at a different spot but it works pretty well where it is.  Attached to the boosting fan is length of 4" PVC that runs the length of the floor joist.



If you are wondering, yes that is 14-2 standard wire.  It has since been replaced with 14-2 flexible outdoor wire.  I used duct tape again to seal the PVC connections to the boosting fan.  The long run of PVC was secured to the floor joist at each end the same way the PVC elbow was secured.  The 4" PVC run took me to the tricky part of the project.  I had to get the air from my future rec room, across the whole basement to where my furnace and dryer duct are.  I had already boxed in my furnace duct work so I figured I could run a line next to the existing duct work without any problems.  I used a modified funnel to taper the connection from the 4" PVC to a 1.5" flex hose that would carry the air the rest of the run.  The braided flex hose creates a bit of an issue in terms of extra head pressure but I really didn't have much choice at this point.  Here's the funnel adapter and it attached to the PVC with duct tape.





I don't have any photos of the termination of the whole system but there is a T connection with valving on each of the branches that allows me to run the air to my cold air return on my furnace during the winter or to my dryer duct during the summer.  The whole system doesn't move a lot of air but enough that I think the humidity in the main room of the basement won't get out of control and it should help cool the lighting a little bit.  It may have just been an interesting project and not particularly useful, but I figured with this setup I might as well go for everything I can think of rather than get the tank going and wish I had this or that.

[Vincenzo.]

good idea man. is the fan loud/noisy? will you need to insulate? pipes will sweat from wet air. or even inside the pipes. especially pvc and metal.

you might get some sweat right where the fan and pvc meet. and dont want to take any chances with sweat dripping back onto your fan, possibly wetting some wires. and possible short when the fan comes back on?

(since i recon you will not be running this fan 24/7)

idk if this makes sense. but i dont want anything to happen early on in the build. that might be a problem later on down the road.

[Consigliere]

There may be some condensation on the inside of the pipes, but sweating only happens when the temperature of a surface is lower than the surrounding temperature.  This lowers the dewpoint at the surface and causes condensation on the outside.  In this case, the pipe will always be warmer than the surrounding temperature so the outside sweating will not be an issue.

As for noise and vibration, there is definitely a bit of both.  It isn't too bad right now with the drywall installed now and once the hood is in place for the tank I imagine that will dampen the noise and vibrations a bit as well.  If it is too noisy then I will only run it at times when no one is home but hopefully it won't be too bad and I can run it whenever necessary.  I will likely run it minimally at night and probably run it intermittently while the lights are on.

Hopefully it works out, if not it cost about $40 so no big deal if I never end up using.  Just didn't want to get this all going and look back and wish I had an exhaust.

[Vincenzo.]

okay thats good. good you cleared it up. ad hope it work out well. yea i guess once it's more in closed there will be less noise to worry about. with a tank that big, im sure there will be some buzz and hum's.

[JD]

I tried using one of the booster buct fans to help move in in my old house. I bought one of the expensive two speed ones. I found it noisy and did not move much air at all. It lasted a month and a half in 24/7 service.

Do you plan to run your furnace fan 24/7 when exhausting your humid tank air into the cold air return? Please consider the possibility of mold growth if the fan is not running on the furnace, especially if your duct work has not been cleaned out recently.

A trick I learned awhile ago dealing with fan noise, if it's an issue, is to use a basic light dimmer switch on AC fans to vary their speed. Different voltage power supplies on DC fans are a suitable way to slow them down.

[Consigliere]

I never considered the possiblity of mold growth when exhausting into the cold air return.  That is a great point.  I may have to exhaust it outside all the time.  That was my original intent but thought if would be worthwhile putting to the cold air return to improve furnace efficiency. 

Thanks for the tip on the dimmer.  That would be a good upgrade I'll have to look at.

[veron]

I always suggest a person consult with an HVAC tech before exhausting anything in a house. your changing the dynamics and pressure. it can cause more headaches or death if your not carefull.

[redbelly]

The concerns that Vernon is refering to here (I think) are with respect to venting to outside.

Don't quote me on these numbers but I believe you should not vent out of the house at over 700 cfm total. This include the fan over your stove. Even on the high output or large stove fans, some of them require a fresh air intake as they do in fact exceed 700 cfm on their own.

The risk is that by creating a negative pressure you can drawn the exhaust air inside from your furnace.

On older houses with windows that leak air anyways its not really going to be an issue, but on a newer place (such as my place) that seals tights as a drum it can be a concern.

[Consigliere]

Thanks for the information here.  The entire system doesn't move much air because of the long run of flex hose.  I would estimate maybe a total of 20-50SCFM.  The system will only run for a few hours a day as well so the total should not be an issue.

The more feedback I receive though, the more I think it isn't wortwhile utilizing the exhaust into the cold air return.

[sdivell]

I'm going to jump in here as I do have experience in home design and industrial mechanical designs.

No, its not worth venting into cold air return in the winter, here is why.

In the winter the basement is exactly where you want that warm, moist air.  It will then rise up through the house forcing cold air back down into the basement for heating by the furnace.  The only way to properly recover warm air is with a HRV unit in the house which takes the heat out of the exhaust air (but not the air itself) and heats up incoming fresh air.  If you do have an HRV installed in your home (and most new homes do), venting this tank exhaust into that would be worth your time and a good idea.

My advise is save this exhaust for summer months when you really want to pull that moist air out of the house.

[Consigliere]

Great info here.  Thanks again guys, really appreciate the feedback. 

[Vincenzo.]

what about running a de-humidifier? You can have it on a timer for maybe 2-5 hours a day while u are at work.

[OttawaFolkFestivum]

Good discussion here.

Would be interested in hearing about the tank supplier decision making process that you alluded to in your first post.

[Consigliere]

Let's just say the tank supplier promised a delivery date, and then missed it by 5 months.  Not saying he was lying necessarily, but you would expect a 50% deposit at least buys you a firm delivery date.  I was told that originally by a few people but he came in at lowest cost by over $500, and was half the price of some other quotes.

I still haven't actually received the tank so I can't say anything about quality yet.