shop vac = think of a regular vacuum cleaner you use to clean carpets with. they normally have a little hose / nozzle you can use to clean up in tight corners and on furniture. a shop vac just has the hose / nozzle. and tends to be more powerful (bigger motor) than a standard household vacuum. plus most of them has 2 inlets. one for dry stuff, and second for water. for say cleaning up a wet basement. most of the shop vacs. the outlet on them. you can place hose in. and turn it into a "leaf blower"
Did not know it is a vacuum cleaner... the shop vac. I just saw people using compressors In South Africa...That is why I settled for it...Will go to our Biggest shop and take pictures of any thing that blows air and looks like a industrial vacuum cleaner. Posted ones already pictures of what I found....
EDIT: above describs WET/DRY shop vac. there are just "dry shop vac"
most wood working shows on TV. tend to use a dedicated central vacuum setup. to suck all the wood chips and dust to. but majority of large tools, table saw, chop saw, etc... have a "dust collector port" on them. some may just have a little bag to collect dust / wood chips. but for smaller shops (regular folks) may just use a "shop vac" connected to the dust port, to keep dust from going all over the place in the shop. hence "shop vac"
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retro drain = a dome with a pipe coming into the side of it. and normally a 3 to 4 feet to hold dome up off the floor.
See pic 1 . Those are all the fittings available here... From 2 of the biggest shops, that specialize in fittings...And trust me there is no shop where they sale fittings that I have not been. The only one I found that is suitable the pipe is on the bottom, not on the side, add a bend....and it becomes too high...not suitable... I built my pond without BD... Did not know much about ponds...so what I did is I put a perforated pipe on the bottom, that is working very well, but the pump sucks from it...so I have a sand filter after the pump for that reason that is cleaned every day. I have a number of pictures on how to do a DIY retro drain...for the pond I am going to build it will work, since it can be under the concrete, but for the intex...not.
what is a dome? 5 gallon bucket cut down so it is only a few inches high. or it could be a "large bowl" from your kitchen. it could be anything.
what a dome does..... instead of water being sucked directly into end of a pipe and from one direction. a dome spreads the suction point out and around. this also causes a larger suction area to be created. like vacuum nozzles were you have a little nozzles to get in between couch cushions vs a larger size nozzle for say steps or carpets. the dome = larger nozzle.
generally the "gap height" distance between bottom edge of dome and floor of pond = approx 1/2" give or take a little.
www.worldwidekoiclub.org -> pond building info -> (forget links to click) it is one or two more links. to find "retro bottom drains" or rather a bunch of links to builds here on koiphen for retro bottom drains.
I think I know all those threads by heart...now...I tried to learn and understand it all...Very good info there...some a bit....misleading foe dummies,
all ya need is a large bowl for a dome, some glue or silicon or polyurthen some legs could be pieces of plastic or end caps or something. and cut a grove in dome for the pipe or how ever you want to connect the pipe to the dome.
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FRY
what ever you use, fry are going to end up every were more so if they are eggs still. in filters, in pumps, etc... if you are placing submersible pump in pond. good chance a good amount of fry will be killed. and you would be better off creating a foam pre-filter box.
What I thought of doing is...Put the pump when the fry is a little bit bigger, and then use a laundry basket tall one , with very large holes, made out of rigid plastic, and a mosquito net netting around the basked tied on top around the pump...so that it is not sucked into the pump, and use that until the fry isaround 2" to be on the safe side...The grill on the pump is 1cm....so if the fish is larger than the holes it will not be a problem (I hope) I know a submersible pump is not the best...but I have it and instead of buying another pump...I thought of economizing... My fish started breeding nd they are at it every 2 weeks...so I build today a concrete base for a second intex pool....They will bankrupt me. That one I will set up with an external pump (I have it but it is a bit too big and keep it as spare for the pond...) there I will go the normal route...sediment chamber, mech filter...bio...returns...maybe add a bakki if I use pressurized sand filter after the pump. But I am trying to economize as much as possible...
other words a plastic box of some sort with a bunch of holes drilled or slits cut into it. then pump placed into it. and then a bunch of foam put around everything. this will keep fry from getting into the pump.
if you are placing pump in another external filter. then highly advised to have a settling chamber, with static basket. between outlet on pond and pump, this will make it easier to bowl / net out the babies. and ensure more are kept alive.
above is most likely getting overboard. *but shrugs*
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fittings.... that i do not know about you being in zambia. here in US. most hardware stores have slip to thread fittings. and then bushings or reducing couplers. that allows you to go from different sizes fairly easily. along with different "thread patterns"
if anything you should be able to pickup say a "barbed" fitting. and cut off end of an air hose. and pipe clamp it on. and then attach to air cleaning manifold. and then use a quick connect or like to air compressor.
This I dont understand...but I am guessing what one end of the barbed fitting is...I will just need to improvise...some how, and I am getting very used to that of late...
barbed ends look like the ends of the TEE's you are using now for air ring.