Central Filtration System - Need Help Please!   7/31/11
Hello. I am new to your site but have been reading it over and over again looking for answers to my questions. I cannot find them,
<Please read here: http://wetwebmedia.com/AqBizSubWebIndex/cntfiltbiz.htm
and the linked files above>
so I am writing to you to see if you can be of any help. I am building a central filtration system sump for my fish tanks (livebearers). I want to have all my tanks filtered through a shared sump.
<Can be of benefit...>
The sump will be set up where the incoming water will first flow through a UV sterilizer and then flow through a tub filled with live rock and then there will be a sponge filter on the return before the water is pumped back out. I will also have a heater in the sump to heat all the tanks water - not sure how big it needs to be.
<The bigger the better... do use submersible heaters... perhaps an added controller for safety.>
I will have approximately 12
- 20 Gallon tanks and 14 - 10 Gallon tanks on 2 - 2-tier shelves. I plan to drill a hole at the bottom of each tank and stand a pvc pipe up through the hole of the bulkhead. I plan to drill holes at the top part of that pipe and put a sponge filter over the top to keep the fry from being sucked through. My question/worry is that I cannot figure out what size bulkheads to use and what size pump to use.
<This is all covered on WWM... do you see the search tool listed on every page?>
I'm worried because I do not know how fast the water will drain from the 26 tanks and I do not know how fast the pump will pump the water back into the tanks.
<... oversize the overflows...>
I purchased a Rio 20 HF pump that states it has a flow rate @ 1 foot head pressure 1290 GPH and flow rate @ 6 feet head pressure 870 GPH and the inlet is 1" pipe or 1-5/16" hose and the outlet is 3/4" NPT or 1" hose. I plan to have the water returned to the tanks with pvc pipes running along top the tanks with a pipe running down into the tank coming close to the bottom to help swirl the water around to help drain out some of the bottom water also.
I've also heard of using drip valves but didn't think they will provide enough flow to the system. So my main questions (I guess) are what size bulkheads should I use for draining?
<At least 1" ID>
What size tubes/pvc pipes should be used for the intake and the return of the water from the pump?
<The size/diameter of the fittings on the volute...>
What size pump should be used - did I get the right one?
<Can work>
I was thinking 1 1/2 inch bulkheads for the drains and 1 inch tubing for the return. Am I way off? Am I missing something?
<Please read here: http://wetwebmedia.com/BulkheadFloRateArt.htm
and the linked files above of interest, pertinence>
Any kind of help would be great. I know how I want this set up (I can picture it in my head) but I just don't know how to do it. Thanks so much!!
Melissa
<Do put all your plans in writing, including the stand design... and do write us back w/ your specific further questions, concerns, after you've read the above areas cited. Bob Fenner>
Re: Central Filtration System - Need Help Please!   7/31/11
Thank you so much for your help. I've read the articles sited - sorry I didn't find them before.
<No worries>
I'm starting to understand a little better now but after reading further, this question comes to mind - I apologize if this sounds like stupid question - let's say for instance the 2" bulkhead will flow to sump 1350 gph, but I have 26 tanks with the 2" bulkhead, does that mean each tank is going to flow 1350 gph into the sump, meaning I'll have (1350 x 26) 35,100 gph flowing to the sump.
<Mmm, no... with the total flow you state... divide each tank into it...
1/1,350th per hour... a one inch ID through put/bulkhead will do>
I know that just doesn't sound right but I'm wondering about it.
<...? Each tank will have a (ball) valve...>
What I've read so far is that using a bigger bulkhead is better. But do I have to use smaller bulkheads because I'll have 26 tanks all flowing to the sump at once? I guess that is what is confusing me - the multiple tanks all flowing into the sump together.
Although I've also learned now that when I add the sponge filter to the end of the pipe, it will drastically change the amount drained.
Thanks again for the help!!