Overflow choices?

I'm considering getting a tank with an overflow, as I don't trust the HOB
overflow box I have. The GF are big enough now, that they can/have knocked
the overflow loose. Besides it will give me an excuse to upgrade the
tropicals.

So I'm wondering about the different overflow options. I've read that the
tanks with the built in overflows (floating ball) are less than desired. The
LFS seemed rather keen to sell me a ready made overflow solution, rather
than drilling a new tank for me. They also said they can only drill the back
of the tank and not the bottom. They wanted $300 CDN for a 90 gallon premade
overflow solution. I imagine a plain 90 is somewhere around 150 + cost of
drilling if I go this route. Then I would still have to buy the overflow, so
$300 seems reasonable. I'm not in any real hurry, so I could wait for a used
tank.

Opinions please.

"Bill Stock" wrote in message
...
I'm considering getting a tank with an overflow, as I don't trust the
HOB overflow box I have. The GF are big enough now, that they can/have
knocked the overflow loose. Besides it will give me an excuse to
upgrade the tropicals.

So I'm wondering about the different overflow options. I've read that
the tanks with the built in overflows (floating ball) are less than
desired. The LFS seemed rather keen to sell me a ready made overflow
solution, rather than drilling a new tank for me. They also said they
can only drill the back of the tank and not the bottom. They wanted
$300 CDN for a 90 gallon premade overflow solution. I imagine a plain
90 is somewhere around 150 + cost of drilling if I go this route. Then
I would still have to buy the overflow, so $300 seems reasonable. I'm
not in any real hurry, so I could wait for a used tank.

Opinions please.

My experience is quite limited, but my preference is back drilled custom
tanks. Back-drilled on regular tanks can drop the waterline into your
sight-line, whereas custom tanks can be made with the back pane taller,
or a deeper plastic trim to hide the waterline. Standpipes (bottom
drilled) can be noisy (I heard if you insert a slightly smaller pipe down
the centre, you can quieten them). Back-drilled can be noisy but they
are easy to quieten down by angling the plumbing. That's all I know.

What I haven't seen is a combination. Bottom drill without a standpipe
and install a sheet of glass to set the water line. The glass could be
set diagonally in a corner, or run the length of the tank (depending on
how else you wanted to utilize the space, ie: heating only or matt
filters as well). This has the advantage of not being so easy to clog
with floating plant matter (hole is at the bottom of the tank), does not
utilize any screen which can get clogged, has a large surface area for
the water to cascade over (unlike a standpipe), and would probably run
very quietly.

Most designs will 'eat' fry and floating food. One design I liked took
water into a corner tower mostly from bottom grills into an empty chamber
(for optional chemical filtration), then through top grills into another
chamber (for the heater), until arriving at the 3rd chamber (where the
sponge filter was installed, but it could've easily have been a back or
bottom drilled overflow. I liked the design because it took the water
low and high, not taking too many fry, and had many wide grills which
didn't clog too badly (and were easily visible), and the whole thing was
just pieces of plastic (cheap to make).

Hope there are some ideas in there. Sorry I couldn't be more helpful,
but if you google, you'll find several sites which discuss options in
more detail, like this one :
http://saltaquarium.about.com/od/diysumpsoverflowboxes/
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www.NetMax.tk