Backyard Aquaponics
A place to discuss aquaponics

Not all of us. I've been running my system for two months with a 17k LPH pump with no glue.

I can see merit for post as I am about to move system to a permanent spot, and will then glue.

Dangerous game I know, but no issues thus far

Ahh, yes. Called a ring manifold. Very good for lots o reasons.

That would be the optimal idea Bcasey2703, but that would also depend on your setup, I don’t think my grow beds could handle any more water than what they are getting now, and the extra piping in my case would be an expense upfront that would be easily covered later down the track, but not at this point in time,
As for the others! There are many parameters other than just the size of your pipes to calculate water flow, yes bigger pipes allow more flow, but you still need the pump pressure or height of gravity to produce it,
The best way is to test the water flow in three timed test over two or more timed intervals, like 10sec 30sec 1min, offcourse if you cant hold the amount off water flow in one minute then use the first two test and average them out then multiply them to the factor off one minute, that will give you the actual flow of your system at any point, you wish to test, that’s how I worked out the amount of water going through my fish tank and filter per hour, which is now over 10ltrs per minute, using 25mm pipes gravity fed, with about a 200mm drop from fish tank solid lift pipe to sump tank return pipe,

There is no need to estimate your flow if you just test it, unless you are in the market for a new pump,

Fair enough although 1.5m/s is still rather fast.

I understand what you have written but I don't understand the point you are trying to make.

For me it's not so much about pressure, but increasing the height I can pump, whilst still having low outlets. I want to add some 1m high vertical towers, but keep my excess to sump tank for the extra O2. Might have to re-do plumbing so excess flow is highest point.

Will stop the hijack now.

I like this thread, but sometimes it feels like there is too many variables at time to do anything other then have a crack, and post results!

Its all related. Pressure and height are almost synonymous. You get height because of pressure. The pressure provides force which works against gravity to give you the height.

To have low outlets you have to restrict them. Essentially what you create with a restricted low opening is friction that the water is having to work against. The water takes the path of least resistance. If the restriction is such that the friction, back pressure or head loss (all kind of the same but slightly different) through the restriction is more than the height of the upper opening then you will have water going out the upper opening.

Cool, makes sense. It's looking like rain next few days, but need a rejig I reckon once that happens. Hopefully still on topic enough to be ok for this thread, but if adding some extra piping from 25mm existing that I want much smaller (ie to vertical towers needing small flow) what's best option in everyone's opinion? Solids shouldn't be an issue as it's coming from sump which has good filtration to it?

Have you thought of maybe a water tank reserve above your towers? You could slow release your water from above using the tank and a few taps, a steady constant supply of water from your pump would not be as much off a burden as the water would just be diverted to the top tank, I am running a pressure relief valve now on my system, that water would easily go up to a top tank if I was to want one, but I will be diverting that to my channel system when I find the cash,

Its just an idea! I have them sometimes,

Yeah great idea, not ideal for my situation though.... Thanks

I have gone 15mm to my grow beds, I have a 20mm pipe from my pump to a threaded tee section that’s 25mm, that one side goes to the fish tank and the other hit’s a reducer into 15mm pipe after passing a tee joint with a pressure relief valve added, I don’t think I can get any smaller than 15mm pipe here unless you go 12mm rubber hose,

But do rethink the top tank idea, it would only need a 90mm pipe with two end caps and a possible overflow? A constant drip feed to your plants, gravity fed,

Thanks Blizzard, going into a fairly specific and limited (design and "pretty" terms anyway), so no option for a top tank currently.

It's in plan if I ever get to make a big system, as a real good friend of mine is an electrician who specialises in solar, and that's one of his "big plans" for my systems long term ahaha.

If there is a big difference in height it may be worth having 2 pumps, one for the beds running a low pressure and hi flow, Then in the towers a high pressure low flow pump.

If you have one pump and throttle the flows to the beds so you get the water up to the towers you will be wasting power and pump life. Sort of depends how big your system is I guess but the GB's will probably have a large flow and the towers a smaller flow.

I've got an 18000lph pump, I'm assuming I'll always have extra, which I pump back to sump for aeration. Not a huge difference in height, about 50cm, so should be fine? For me it's about getting my head around all aspects in a general sense, as I am paying a bit extra power wise to have extra LPH, so am trying to stay away from air pumps.

I had a bad experience with air pumps in keeping fish tanks, seems to have scared me for life ahaah, extra literate back to sump and venturi's are my prepared method.

System will be upgraded to 5-7 300l GB, 3-4 1000l FT, 1000l sump in the next month, leaving myself options for DWC, vertical towers, NFT etc etc. FT's won't be overly stocked, I just want variety. I'm using IBCS.

thanks

Bcasey, you are not highjacking the thread talking about pressure as it is all related.

Thing about putting a water tank above your towers means you will have to pump water that much higher. Water is heavy so it gets costly to lift, increasing the height you can pump will increase your pressure there is no getting around that one

It shouldn’t be too difficult checking if your pump is strong enough to lift that water by connecting a hose somewhere after its outlet then put that hose at the height you want and measure the output into a bucket.

You are right Stuart “1.5m/s is still rather fast” a BYA system should never ever get to those velocities. As you said move your water fast enough to keep solids in suspension I think undersizing piping to save money is not the way to go.