The upper vent in your uptake, on your filter, is your's open, closed or partialy opened and why.

The upper vent on your uptake? What exactly are you referring to? The flow limiter on the inlet of your HOB power filter?

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Officially fishless until after the move....tune in later for details!

I have an Emperor 400 HOB filter, onthe intake tube that sucks the water into filter there is a little vent about half-way up, I assume thats what your referring to? I keep mine closed so that I get as much suction from bottom of tube as possible, I just think its better that way and you get good circulation. but I would be interested to see what others do.

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90 gallon, 1 Iridescent shark, 2 Pleco, 3 Goldfish, 5 Cory cats, 2 Nerite snails
5 gallon hex, Blue Crowntail Betta, 1 nerite snail,

I don't have one of those, sorry.

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Officially fishless until after the move....tune in later for details!

My filters have a different kind of flow control, but I always leave mine wide open.... I find it filters more water per hour and keeps the tanks well aerated. I don't mind the miniscule bubbles that it makes in the tank (even though it looks like dust, lol.)

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20g Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981
36g Bow Front Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981

mine dont have anything thing like that, i use canister filters though and there full force to get as much filteration as possible

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What happens if you get scared half to death, twice?

I have those on my dual marine land 350's it really does not matter. To me it's a gimmick. I had one filter going way down near the gravel and the other high up without the extension. Got tired of reaching into the 55 to pull stuff of it and put them both high. No changes. I actually yanked off the grey little door on that extension and put them both in as tubes for the fish to go in lying in the gravel. Go figure. And those little grey doors get pretty ugly once they get some algae on them. Again I don't think it's a big deal...the water goes In and the water comes out.

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Hoopman
Sunny Orlando FL
55G W/Angel, loaches/cats, tetras, rasboras, Two Bio Wheel 350's (8 cartridges and 4 wheels) Dual T5 ATI bulbs which are blue & blue-plus (white), give a saltwater tank look/moons. - 37G w/Angel, Mystery snails, tetras/cherry barbs. Dual 24 inch T5 with same ATI bulbs/moons. Bio wheel filter (dual cartridges and one wheel) and Aqueon single filter Bio cage cartridge, both designed for larger tanks. n

I leave mine closed, i feel like it gives me better circulation from top to bottom of the tank. but its all just personal preference

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Tank
125g african cichlids making it work
75g rimless Reef in progress

I'm thinking that it'll reduce the suction on the bottom, not allowing it to suck up sand if the fish kick it up.

mine is closed

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"Being ignorant is not so much a Shame, as being unwilling to learn".-- Benjamin Franklin