OK, so I am looking at the designs and it looks like I need 4 PVC pipes. Three for the bean animal and one for the return. Five pipes if I want to automate my water changes.
I was watching a bunch of videos (and really trying to understand the Hazen–Williams equation, and this one did a great job of explaining the Bean Animal setup
, but at the 5:15 mark, they start talking about the size of the piping saying that for 1500 GPH or less
, use nothing bigger
than a 1" pipe, but in looking at some flow charts for 1" PVC, that seems like it might be a bit small. This chart says that the max flow out of a 1" PVC pipe via gravity is only 600 GPH and I only need a 9" drop to get maximum flow:
However, this chart from FlexPVC.com seems to show that 1" via gravity will support 960 GPH as opposed to 600 GPH:
seems to support the 600GPH limit on 1" PVC as well.
So Rex Grigg suggests here
that 5 to 7 times turn over for a planted tank is what we should shoot for. My current tank is a 75, and if I added a 40-gallon sump (that I can eventually use on my 210) I am looking at 575 to 805 gallons-pre-hour I would need to be able to manage. In the youtube video above, he says anything less than 1500 gph stick with 1" but in the chart, it says 1" will only really do 600 gph.
Which is correct?
Given that I will eventually move to a 210-gallon tank, I would need to target closer to 1250-1750 GPH (with 1500 being a good spot based on the pump I want to get) which means that I need to move to 1.25", but going back to the video, they seem to be saying that if you go too big on the siphon line you won't be able to get a full siphon. I guess I really only want to run this piping once and size it correctly all the way around.
For my return, I am looking at the Iwaki MD-100RLT. I calculated my head pressure to be about 21' based on 1' per vertical foot, 1' per 10' of horizontal piping and 1' per 90 connectors as suggested here
. With the 100RLT and 21' of head I can get 1500 GPM with a 1" return line:
Does this pump seem reasonable for what I am looking to do?
Lastly, I am concerned about my log horizontal run which in my case will be about 23'. According to this website
, it says to avoid horizontal runs longer the 24" or I will have problems pulling a siphon.
suggestion, I took a 5-gallon bucket and set it up 20" higher than another 5-gallon bucket and using a 5/8" 30' garden hose I was able to get a siphon going and keep it going with the horizontal run wth no problems, but as I said above, I would rather figure it all out ahead of time before I install a bunch of PVC that does not work!!