Flow Rate For Bog?? [to yield optimum filtration benefits]

[Mmathis]

Are there some rule-of-thumb GPH numbers for this? And what advantages are there for fast vs slow? Where do the sizes of bog & pond, as well as the diameter of the tubing come into play?

Looking for what will give me optimum filtration flow through 2 bogs [see below] -- but not sure what OPTIMUM is in this case. Slow, fast....?

Trying to get some idea before we proceed. My stats:

• The pond is roughly 3000 gals. -- gold fish
• I just finished a small [3' x 6'] bog for my box turtles, but it isn't connected to the pond yet -- PVC distribution pipe used was 1 1/2".
• the main bog will be something like 10'-15' x 4'-6'
• not sure what size PVC I'll be using for the main bog..... either 2" or 1 1/2"
• my pump is a 3600 gal. GPH solids pump [from Home Depot]
• I previously ran this same pump to both my SKIPPY filter and the OLD turtle bog -- it MORE than moved the water adequately, and I actually had to dial it back to both the filter and the bog.
• once both bogs are up & running, SKIPPY goes bye-bye

 

[dieselplower]

When talking about mechanical filtration, a slower flow is better if you are looking to filter out as much debris as possible. A slower flow is also better when talking about biofiltration, because it keeps the water in contact with the benificial bacteria longer, giving them more time to do their job. There are articles out there that give specific information as to how much time the water should spend flowing through a filter if you are looking to maximize results, but I am at work so I can't dig it up right now. I want to say if you can keep the water in the filter/bog for about 45 seconds as it flows from the input to output, that would be close to what the article said was ideal. I really dont recall exactly though.
Of course the trade off to a slower flow is turnover of the pond. Turning that pond over once per hour should be more than enough.

 

[addy1]

My pond turns over around every 2 hours or so. The pump is around 6500 gph going into the huge bog. It has worked

 

[dieselplower]

I thought the pond was 3000 gallons? 6500 gph pump would turn the pump over twice per hour. Am I missing anything?

 

[Mmathis]

I thought the pond was 3000 gallons? 6500 gph pump would turn the pump over twice per hour. Am I missing anything?

Two different people -- that was Addy with the 6500 gph pump. Mine is 3000 gal pond with 3600 gph pump.

 

[dieselplower]

Haha yep missed that!