Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!hoptoad!amdcad!decwrl!gringort From: gringort@decwrl.UUCP Newsgroups: alt.aquaria Subject: Reverse Flow Undergravel Filters Message-ID: <168@bacchus.DEC.COM> Date: Thu, 3-Dec-87 16:51:52 EST Article-I.D.: bacchus.168 Posted: Thu Dec 3 16:51:52 1987 Date-Received: Sun, 6-Dec-87 20:08:31 EST Reply-To: gringort@decwrl.UUCP (Joel Gringorten) Organization: Digital Equipment Corporation Lines: 8 What do folks think about reverse flow undergravel filters in marine applications. The general concensus I've gotten elsewhere is they can't be beat if they're done right. The advantage primarily is that the substrate is kept very clean because water is forced thru the substrate from the bottom up. A key element in this technique is to use a large external mechanical filter and a large pump. -- -joel