Backyard Aquaponics
A place to discuss aquaponics

If you haven't bought your pump yet and you're planning on aerating the water in the tank with any excess pressure... then I would be putting a much larger pump than 500Lph in the system. Most 500Lph pumps stop pumping at about 1.0 - 1.2mtrs, and your GB is probably about 0.9 high. You can factor in the water head in the tank, but I think a 500Lph pump won't allow for any excess pressure for tank aeration etc.

Mr Damage.

You may be right Mr Damage. I might get a 600L or 700L pump then. I think the return alone should be enough for the fish as aeration but i could add a single air pump with battery back up just in case.

With a spray bar I would go the Aquapro AP750 as a barest minimum, the AP950 would be my personal choice, only 18w and about $55.

Isn't head measured from the top of the water level in the tank to the top of the grow bed (even if the pump sits on the bottom the tank)? That wouldn't be anywhere near 0.9m.

Still wont be any where near 0.9m so a 500 litre pump should be a good fit, specially if it's a very low wattage.

Just skimming, looking at pictures, not sure if anyone else has told you this but you actually have to take the claypebbles out of their bags for the GB to work properly.

I didn't say his head would 0.9m!... but let's just say for arguments sake (seeing as you appear to be intent on having one) that his total head is only 50cm... have a look at the flow chart below for an Aquapro 550Lph pump (bigger than the 500Lph you assured him will work)... at 0.5m head the flow is only 170Lph... and that's before allowing for pressure and flow reduction due to pipe and fittings etc, plus he's going to want some spare pressure/flow for aeration.

I'm only trying to spare him the hassle of buying and underpowered pump and wasting his $$$!... why not buy one that will definitely do the job... and have plenty of flow/pressure to spare so he can then by-pass that extra flow/pressure for aeration?... and I can tell you from personal experience... in that system, a 500Lph pump will not enable him to do that. He may just be able to get an auto siphon working (if he's lucky)... but he will not have anything to spare!

The difference between a 550Lph and 750Lph is about 3x the amount of flow at 0.5m... but only 1.5w and about $10

http://www.aquatecequipment.com/products/submersible-pumps/2/brand/aquapro/2

Yeah, the smallest pump we have is 1250l/h and I don't think I'd ever go for a smaller one, even for a tiny system like this one. Once you have pipe resistance fittings etc. Man, even the 1250l are such a tiny pump physically.

With guppies and glass shrimp being so small will a bigger pump suck them into the GB

In that case I'd go the AP750, or similar, not the AP950... and ask your pump supplier for an external foam filter, it's a block of spongy foam that you slip the pump inside...

or, just leave the external filter out of the equation and test Darwin's theory about only the strongest and smartest surviving... you'll end up with super shrimps!

Another thought... suspend your pump up of the bottom of ther tank. You could do this by shortening the hose and make sure you clamp it on securely, or sitting the pump up on a brick. That way the shrimp and fish will be able to rest on the bottom of the tank without fear of being sucked in.

Thanks for the discussion Mr Damage. I don't think I was ever argumentative. I asked a question and gave an observation. You answered that question - thanks.

I never assured any one that it *would* work - I said *should*. You have read my post like I have read yours (stating that most 500Lph pumps stop pumping at 1.0 - 1.2m and then saying the growbed is 0.9m really does look like you are saying the head is 0.9m)

Thank EB for putting it in a way that this idiot understands.

To Zman: It is a great little system. It would be cheap, simple and quick to make. A great beginners system, hospital tank, live feed breeder system or a system for people who dont have a whole lot of space.

Fair enough!... I can see what you're saying... I should've just left the 0.9m bit out of my first post.

Oh shit really? I think I better go attend to my GBs

I just found out you actually have to feed th fish too, they dont grow by themselves