Bog flow rate calculator
- Thread starter Crash78
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I would say: as slow as you can while still turning over all your water fast enough. Is your bog your only filtration? What size is it and what size is the pond?
Do you already have a 2,000gph pump going to the creek?
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you were advised; as few/slowly as possible without jeopardizing the pond movement. So, you could get almost any size pump and use that. That said, most send a decent amount through their bog. I have a 180 cu ft bog and send approx 4000gph. I've also done half that. My current setup uses the bog for visual effects, i.e. a waterfall, so I send more than is necessary. You're not going to hurt it by sending too much; the plants and bacteria will take what they need. If too much goes up and past, it'll just end up getting back to your pump to do so all over again. If you're using a 2000gph pump, if it were me, I'd wye off and send one feed to the bog and one to a waterfall/filter. If the waterfall isn't pouring as you wish, then I'd get a secondary pump of 1000gph to supply your bog. You can always wye this off and put ball valves on each feed, giving you ultimate control over how much goes into your bog. If you send 'too less', your plants will probably alert you first by showing yellowing leaves in that they are not getting enough nutrients. We seldom have this problem here, though.
You have to understand, 'maximum filtering' is momentary. Once the plants start filling in and the pea gravel gets a bit clogged, you no longer ever have 'maximum'. You do have adequate or even great filtering, though! Your bog will have a faster flow through in the spring before the plants really take off and less so in the middle of the summer when they're established. It IS recommended that you prune back the plants every so often as this promotes more vigorous root growth and that is where their part is played out best. Everything else re your bog is bio in nature; the bacteria will colonize and convert the ammonia and nitrites.
You have to understand, 'maximum filtering' is momentary. Once the plants start filling in and the pea gravel gets a bit clogged, you no longer ever have 'maximum'. You do have adequate or even great filtering, though! Your bog will have a faster flow through in the spring before the plants really take off and less so in the middle of the summer when they're established. It IS recommended that you prune back the plants every so often as this promotes more vigorous root growth and that is where their part is played out best. Everything else re your bog is bio in nature; the bacteria will colonize and convert the ammonia and nitrites.
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Sorry. Meant to reply. Best practice seems to be to shoot for 10 min. dwell time in bog filter. Longer is better if possible. Shorter works too, but less efficient. I imagine most people who build them have no idea what their dwell time is, and don't care either because it still works. They're very forgiving.