From: livings@unislc.uucp (Ross Livingston)
Subject: more DIY w/d questions
X-Newsreader: Tin 1.1 PL5
Organization: Unisys Corporation SLC
Date: Wed, 2 Sep 1992 15:25:24 GMT

Ok, I've come a long way in my wet/dry plans, thanks to lots of help from
many of you.  I still have a few questions though.  Hopefully, in about a
week, I should have this thing pretty close to done and I'll post detailed
explaination of what I end up doing.  If all comes out as planned, I should
be able to make this thing for about $85 US.  This includes the price for
the pump (Aquaclear 802) and for an acrylic skimmer (surface, not protein),
complete with prefilter (you know, the two piece thing with the skimmer
inside the tank and the prefilter hanging off the back).  This does not,
however, include the cost for a bio medium.

Now, some questions:

1) Is pvc primer and glue (the kind used to join pipes in sprinkler systems,
   etc.) toxic?  I probably won't need glue for the pipe joints, as they
   won't be under pressure, but I have another idea that would require me to
   glue pvc.  If pvc glue is bad, what is a substitute?  Will acrylic cement
   work on pvc, or is pvc the same thing as acrylic?

2) I have heard of many different (READ: Cheap) substitutes for bio-balls.
   I was at my local pet store last night and I mentioned this to the guy
   who was working there.  He said, 'yea, my first w/d was filled with
   plastic plants.'  I asked him what the advantage of the bio-balls was,
   mentioning that I guessed they had a greater area.  He said, 'No, the
   plastic plants I used probably had up to 7 times as much area as bio-balls
   but you just don't get the nitrogen exchange with 'fake' bio mediums.'
   He said the bio-balls are designed so the water is always dripping,
   rather than just hitting the first surface and then running down the
   medium to the bottom of the w/d.  This makes sense to me, but I'm wonder-
   ing if there isn't a cheaper alternative.  The ones he recommends cost
   about $14 US / gallon.  Is there a cheaper alternative, or am I better
   off just biting the bullet and getting these darn things?

3) How much bio medium do I need for a 55g?  I think he recommended 'at least
   4 gallons' of the stuff.  Does this sound about right to you?

4) I hope to cut costs a little more by finding a suitable substitute for
   the so called 'bulkhead fittings', which cost around $9 for a 1" fitting.
   I'm sure similar things must exist in local plumbing stores or hardware
   stores, right?  What am I looking for?  What are they called outside of
   the aquaria world?

5) It seems I read somewhere how to figure out how many g/h your flow is
   reduced by n feet of head.  Does anyone know of a way to calculate this?
   I was planning on using an Aquaclear 802 which will have about 4.5' of
   head on it.  Is it going to perform alright for me?  Is there another
   alternative in the same ballpark as far as price is concerned?  How can
   I estimate it's modified flow (taking the head into account)?

Thanks again for all your help.
-- 
Ross Livingston, Unisys Corp.  |  Phone   (801) 594-6217
322 North  2200 West,   D1V03  |  Fax     801-594-4861 / 801-594-6708
Salt Lake City, UT   84116     |  E-Mail  livings@unislc.slc.unisys.com
Newsgroups: rec.aquaria,alt.aquaria,sci.aquaria