Islands In Big Tanks

[waterdrop]

What do you call those plastic/metal/glass columns that come up inside very large tanks and go all the way from the gravel to the big overhead casing?

 

[T1KARMANN]

i dont know what do you call them plastic/metal/glass columns that come up inside very large tanks and go all the way from the gravel to the big overhead casing?

from what you are saying its a bit hit or miss chould be overflow boxes

 

[waterdrop]

OK, so yesterday I decided to go upstairs in the student union (I work at a university) and have a look at the large aquarium they have there in a sitting area. I'd not been back to see this tank since joining this TFF and learning so much! I remembered it as quite a beautiful tank.

So this time, walking in, I realized it must be 7 or 8 feet long (maybe 125 gallons or more I guess) and my observation was that it was not as beautiful as I remembered (seeing pictures of TFF members tanks, AGA tanks etc. can really spoil you!) It had some bogwood, not many plants and the fish, while large, were not as interesting as I had hoped, but that's beside the point.

Equally spaced out in the middle of the aquarium were these large dark boxes. You could see black hoses angling in or out near the upper edges, looked black rubbery, a little bumpy. You could hear what sounded like water falling.

Your description, "overflow boxes" sounds tempting as the answer. If so, what the heck are those??

waterdrop

 

[Dorkhedeos]

If the box is at the bottom of the tank, it probably isnt an overflow box. An overflow box is a device that hangs over the side of a tank that is similar to a HOB. It pulls water over the edge of the tank out into a tank under the actual display tank called a sump. I am guessing that thing you are talking about is just a pond filter or something similar.

 

[T1KARMANN]

i would say the are over flows they are normaly built in the tank with vents at the top the water is pumped back in to the tank from the sump and over flows back to the sump via the boxes that are called weirs

 

[waterdrop]

oh boy, it gets better and better! So much learning to do...

WEIRS, who wudda thunk it! What a weird word, weirs, I'll have to look it up! Absolutely never heard of that in my life!

In answer to "Dorkhedeos", I think my description was just not clear. The boxes are columns that go all the way up, right on into the big overhead wooden compartment over top of the tank. They have much more the appearance of being overflows than of being filters. They are completely plain with no grills or anything until you get up to the water surface. My observation of what happened at the surface was not so good.. I think the water level was above where the top wood box started so you could only observe the surface from underwater, looking in through the side glass. So I think T1 is right and I was hearing water overflow down to a sump.

I'm proud to say I at least know from my reading here at TFF at least of the word "sump" and that it is an entire extra tank down below that implements filtration of some sort. BUT, of course it brings up so many other questions!

First, back to the fun part.. I should ask if my assumption about the -function- of these islands/weirs is to allow a large tank to be viewed from all sides? This seems self-evident, seems a necessary solution to the concern of not having ugly devices/walls blocking a whole side surface of a tank. In other words, this way a tank can be a big see-through display, right? Am I right about the big-picture reason behind this type of design?

~w~

 

[waterdrop]

gee, while searching about WEIRs, I ran across this interesting place...

http/www.seafriends.org.nz/dda/aqua1.htm#introduction

I know this is about salt water and ocean health and all but the DDA stuff talked about sure seems interesting from an aquarists standpoint. Is this a "known" type thing?

(sorry to be way off track here, but hey!, that's what the blog world is all about, right?)

 

[waterdrop]

OK, I stopped by the student union tank again today for closer observation. Here is more detail:

Each of the two black columns has a series of vertical slots an inch or two long coming down from the top edge. Someone has put screening all the way around to cover up these slots and water pours through these slots with enough force that some small floating plants are pulled over to the screen. On each of the columns, on two of the four sides, the sides facing the narrow sides of the aquarium, not the large viewing sides, there are short black pipes coming out that split into two. This time I observed that these are -output- pipes and water is shooting out of them.

I'm now guessing that these beasts are "internal overflow boxes" and I've discovered a similar looking product picture here:

http/www.wetdryfilter.com/internal_overflow_boxes.htm

(at the first set of 3 pictures as you scroll down, it's the center one in the group labeled "four-sided/center overflows.")

Well, I've now learned a ton of trivia about overflow boxes and weirs, things which I never knew existed or had looked right past in my previous lifetime!

Clearly this big tank has some sort of drilled-out base. Let me know if you think I'm right about this...

~~waterdrop~~.. ps. the students must have thought I was nuts, staring up close at the boxes, not the fish, lol