diy overflows


if you have a tank which is drilled to accomadate a sump system then you have no need for this however if your tank is not drilled and you don't want to drill it then here are an idea for an overflow that can hang on the back of your aquarium.


pvc overflows

as the name says this overflow is made from pvc piping and can be built in a minimal anount of time. basically just follow the design in the pic and your done.





note
- the tee that goes to the sump is located above the internal u this is important to syphoning action
- the black cylinder on the top of the unit is an air check valve this makes drawing the air from the system much easier
- the height of the intake is cut to match the height of your water level
- if you find the overflow to noisy you can cap the vent but make sure to drill a hole into the cap to allow enough air in to keep the syphon going.




how big should my pipe be


the diameter of the pipe depends on the amout of flow you want through your system. ex. if your tank is 100 gals and you want a 4x low rate you would need a pipe large enough to accomadate a flow rate of about 400 gals per hour. also you would need a pump capable of pumping the same 400 gph to return the water to your tank.

below is a chart that give the gravity flow rates of various size piping

pipe size flow rates

3/4" 330 gph
1" 600 gph
1 1/4" 910 gph
1 1/2" 1300 gph
1 3/4" 1800 gph
2" 2350 gph
2 1/4" 2960 gph
2 1/2" 3650 gph
2 3/4" 4450 gph
3" 5280 gph


this overflow design works flawlessly i have built one and an now using it for my sump filter and i've tested it to check if it loses it shyphon in a power outage and when i restored power to the pump it started up again 100% of the time.

the total cost for this ran me about $25 cdn.

hey that looks like a really good idea, and it looks like it didnt cost as much,
HOW ON EARTH DID YOU THINK OF THAT?????

i wish i could take credit for the design however i found this one on the net when i was researching for wet dry filters and thought i'd share it here

well ithink you done a good job copying it, the only thing i dont get is how it will work, ive never used anything like this at all not even a sump, can you describe it alittle better plz m8?????
ash

k well the water enters the inlet inside the aquarium it travels through the overflow and into the sump.the only reason you need the design is to keep air out of the system (therefore keeping the syphon)in the event of a power outage. without this, after the power comes back on, the water would be pumped from the sump back into the tank and without the syphon working would pump your sump dry(since little water would be entering the overflow) and overfill the top of the tank.

because of the design air cannot reach the "u" s in the overflow so it doesn't lose its syphon.(as soon as the pump comes back on the water level in the tank rises and the syphon starts anew).


hope this helps ya

awww i get you now necro mancer i never heaqrd of a design like this but it may be really effective

ashley

the design works flawlessly.i've used it for months now and its reliable. if you change to sump set up and dont want to drill your tank this is the way to go.i'm also working on a design for small tanks (under 90gals) will post when complete...

do you have a pic of it on a tank?

Very interesting necro.. nice post. i am sure this will be helpful to a few people with oscars as filters are a big part of oscar keeping.

im not 100% on how it works!

can any one post a pic or explain?

sorry i dont have a pic of my tank(no camera) however i will be posting pics of the new 250 gallon tank i am currently building and i will probably use the overflow on it. i should be finished in about 2 weeks

ok, kool..

thanks