Technical Question

[Michaelb]

Does anyone know what the maximum amount of gallons per hour you can draw through a 4" bottom drain pipe ?

[vippymini]

as far as i can find on the web its 600 gallons per minute. this could be US gallons though.

[Michaelb]

Thanks for that , that would work out about 36000 gallons an hour

[vippymini]

that just seems a bit fast. i'm sure Bob Hart has a formulae for it.

might be the flow pushed under pressure but i dot think youll get anywhere near 6000 gallons per hour from a pond.

[Bob Hart]

No formula Jane!

Are you asking about gravity, or pulled through with a pump?

I think 3000 gallons is about the max for gravity, maybe a bit more but depends on pipework length and bends. You'll start to drop off the level in the filter if you try much more, sometimes even less will give too greater drop off of level.

If you fitted pumps directly to the pipe, I think I've read you will get over 5000 gallons

[grpjohn]

Surely it must depend on tonnage of water on bottom drain. The greater the depth( head) of water the greater the pressure , although there must be a maximum .I drained my 5000Galls in less than an hour.john

[Michaelb]

Perhaps i should elaborate a little,
I presently have two bottom drains each feeding through 4" pressure pipe one bank of three Vortex's by gravity and then pumped back to the pond.
My plan is to add to Bakki Showers one shower off each drain, there is presently 1800 Gallons being pulled through each drain,i would expect to pump in excess of 2000 gallons over each shower and was wondering if 4" pipe could cope with over 3000 gallons probably nearer 4000 gallons through it.

[Bob Hart]

Michael,

Wether you are pumping direct from the bottom drain to the shower, or even through a seive for each drain, each drain pipe will be more than capable of doing what you want.

Good luck with the showers though, great filtration

[Davej]

Hi Michael

I think that max gravity is 5600gph through 4" ( but may be wrong), I am running 5000gph through a single 4" gravity return from my Bakki this enters the pond at a depth of 3' (so there is some backpressure) and has a head of 12".

So 4000 gallons would not be a problem, you may need to adjust the height of the bottom drain cover, if it is tight then there could be a restriction there.

You may want to think about 3000gallons over each Bakki, the more flow the better from what I am told.

Regards

Dave

[Michaelb]

Thanks everyone for your replies so far, Dave I believe also after talking to Mike that the bigger the gallonage the better it works.Unfortunately as is the case for most, it comes down to economics,so I was hoping to find a happy medium.
At this moment in time I am running two Oase pumps 110 watts each a 55w UV, 700 watt pressure pump to keep the pressure up on my RO unit plus three Airtech 130s and horror of horrors I have an oil burning boiler for the heating !
So the plan is to start off with two showers then finally convert completely to showers ,after reading the appraisals it appears there is no need to run UV's etc unless I am being over optimistic.

It would be really good for me at this stage to get some feedback from people who are using showers .