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addict · 02-21-2004, 01:22 AM

Not only true union ball valves, but schedule 80 true union ball valves...

I can only imagine how many pounds your plumbing cost...

Looks great!

I think the reason the water's rising in your tank is because of the friction of the overflow teeth. It sounds like you don't have enough linear overflow to accommodate the added return flow (or you're right on the edge).

Linear overflow is the capacity of the opening between each tooth, multiplied by the number of openings.

For example, it takes several smaller drains to make up for one large drain, and the overflow teeth mimic several small drains, each being used at partial capacity... as you pump more water into the tank, it effectively uses more of each drain's capacity, due to the extra volume of water draining... the catch is that in order for the water to use this extra capacity, it must rise until the amount draining through the overflow equals the amount of water entering the tank... does that make any sense at all?...

There's a lot of physics and calculus involved... so I only have a rudimentary understanding of how it works...

The only way to really 'fix' this problem is either:
(a) Widen the overflow openings
or
(b) cut down on the amount of flow entering the tank somewhat (which kinda defeats the purpose of the massive flow upgrade).

I don't think the standpipe (weir?) has anything to do with the water height, as long as the overflow is only half full the pipe should be draining plenty... if the pipe was the limit then the tank would overflow... thankfully it didn't...

HTH

02-21-2004, 01:22 AM	#11 (permalink)
addict Reef Lobster Join Date: Jan 2004 Location: Sierra Nevada Country Posts: 1,621 View Gallery Karma Komment	Not only true union ball valves, but *schedule 80* true union ball valves... I can only imagine how many pounds your plumbing cost... Looks great! I think the reason the water's rising in your tank is because of the friction of the overflow teeth. It sounds like you don't have enough linear overflow to accommodate the added return flow (or you're right on the edge). Linear overflow is the capacity of the opening between each tooth, multiplied by the number of openings. For example, it takes several smaller drains to make up for one large drain, and the overflow teeth mimic several small drains, each being used at partial capacity... as you pump more water into the tank, it effectively uses more of each drain's capacity, due to the extra volume of water draining... the catch is that in order for the water to use this extra capacity, it must rise until the amount draining through the overflow equals the amount of water entering the tank... does that make any sense at all?... There's a lot of physics and calculus involved... so I only have a rudimentary understanding of how it works... The only way to really 'fix' this problem is either: (a) Widen the overflow openings or (b) cut down on the amount of flow entering the tank somewhat (which kinda defeats the purpose of the massive flow upgrade). I don't think the standpipe (weir?) has anything to do with the water height, as long as the overflow is only half full the pipe should be draining plenty... if the pipe was the limit then the tank would overflow... thankfully it didn't... HTH __________________ -David *addict's tank specs:* Coming soon! Last edited by addict : 02-21-2004 at 03:47 AM.