How to unclog bottom drain?

[stangale]

The bottom drain has been fine for six years but is now has a reduced flow.
This is a gravity feed that spills into an Evolution Aqua Sieve.
Hooked up the shop vac to suck up whatever stones or debris may be blocking but it just sucks out fresh water at a rate which shows somethings in the way.
The rim around the bottom drain does not appear to have any obstruction.
Any suggestions are appreciated!

[fly4koi]

Run at garden hose and use water? Otherwise drain auger

[richtoybox]

If like my bottom drain was, there was some kind of larva, most likely black fly larva, coating the inside of the pipe. For years, I would tie a piece of string to a cotton mop head and pull it through the piping to clear the inside of the line. I found that Dimilin will kill those larva and the need for the mop head went away.

[stangale]

Run at garden hose and use water? Otherwise drain auger

Thank you.
Need to find a way to make a seal between the drain and the hose otherwise the water will just shoot back.

[delbert]

You could use a drain cleaning bladder .

[rainblood]

Depending on how your pipework is laid out - I've had the greatest success with a regular *** toilet plunger.

I've tried augers and they don't have enough punch to keep the lines cleared. I was this close to buying a water snake jet but the cost kind of slowed me down enough to try a plunger after reading about it here and i'm glad i did

[coolwon]

If you have access to a high pressure water jet cleaner?

You can purchase an end of the feed hose adapter,which consists of a machined brass adapter,with 3 very tiny jet holes to deliver the

high pressure water through the holes at 45 degrees to remove dirt bonding to the inside walls of the pipework you are attempting to

clean.

The brass pipe adapter jets are rear facing to push the dirt backwards at a 45 degrees angle up to scour the pipe surface,which

assists the length of pressure hose to be pulled

forward cleaning ahead and driving the

dirt backwards.

Very, very effective.

No pipe cleaner towing ropes to part company, with the cleaner 1/2 way in the length of pipework.

[aquaholic]

Unclogging a drain filled with sand & dirt is going to be different from unclogging a drain blocked by algae or a dead fish or tree roots.

A flue pipe brush (used for wood stoves) with a nylon rope tied to each end can be pulled forwards then backwards for a great scrub.

A water jetter is great for small blockages. Hire a plumber who also has a camera.

You can buy a drain blocker - some are inflatable, some have a large wing nut screw that expands the rubber base. Tie on a stout cord to plug. Then drain out pipe water from other end. Then release the pipe plug to flush clean. Be very careful not to get an arm caught by water suction as there are internet/urban myths of drownings. On my 2 meter (6 foot) deep tank, I use a 20mm hose for snorkel to clean the sides and bottom. Just remember to breath out through your nose to expell used air. DON'T breath in and out through the long hose as carbon monoxide will build up.

If the pipe is filled with sand & gravel, I would pull a netted scoop through.

[coolwon]

If the bottom drain is partly blocked.

How do you get a rope, you are going to use to pull the un blocker past the part blockage?

[aquaholic]

The simplest way is to use a scrunched up plastic shopping bag tied to twine or lightweight thin cord/strong fishing line if lots of bends need navigation. Water will pick up the bag and work through.

If relatively straight, could try 1mm diameter wire, bend the end over for a rounded stub and gently push, twist if it gets stuck.

I'm fortunate enough to have installed a cleanout path and added a knife valve to gravity purge each of my three drains. The valves are about 1.5m below water line so the force of water is quite astounding. When I close my knife valves after a purge, the water momentum rushes back up the usual pipe path (100mm pipe) and blows the push end cap almost 4 meters up into the air. I prefer that to a screwed end cap that would contain the sudden impact force. My purge path goes into a small 450mm x 450mm x 450mm stormwater pit that has a buried overflow pipe out to the garden. This acts as a gravel /fish trap and I've found lost screws, hose clamps, pump parts etc that I accidently dropped into the tank and small enough to get through the bottom drain barrier so I know the purge works.

[aquaholic]

Apologies to the Original Poster for this side track but the discussion on how to navigate a blocked drain reminded me of air tunnel robots which are simply folded plastic tube with positive air pressure. This concept can navigate ANY small space, can be guided and its potential is only limited by imagination/innovation. Really amazing !!

An example here: https://m.youtube.com/watch?v=qevIIQHrJZg

[stevek]

If like my bottom drain was, there was some kind of larva, most likely black fly larva, coating the inside of the pipe. For years, I would tie a piece of string to a cotton mop head and pull it through the piping to clear the inside of the line. I found that Dimilin will kill those larva and the need for the mop head went away.

I may have a similar issue....will Dimilin break down old deposits, or just kill new larva ? I have several pipe areas where I haven't been able to clean, and I'm pretty sure I have a year to year build up of old deposits. It would be great if Dimilin dissolved the existing deposits in addition to preventing new ones. Also, do you use the dosing listed on the label, or a stronger dose ?

[richtoybox]

I used the label dosage. As for old buildup, that will either take a physical removal or time for erosion/dissolution.

[hacnp]

If you have some flow, I have had good results with letting the flow carry light string like mason line to the endpoint then running a common large sponge (like for tile work) thru. By just pulling it thru. This is on 4" drain line. Best of luck!

[fishee]

I tried Dimilin but that didn't clear all the midge fly larvae stuck on the inside of the pipe. I bought the dryer vent lint remover tool on Amazon and that did the trick. Just be careful not to set your power tool to counter-clockwise as that will unlock the extension sticks and the brush head will be stuck in the pipe

[stevek]

I tried Dimilin but that didn't clear all the midge fly larvae stuck on the inside of the pipe. I bought the dryer vent lint remover tool on Amazon and that did the trick. Just be careful not to set your power tool to counter-clockwise as that will unlock the extension sticks and the brush head will be stuck in the pipe

Do you know if this brush can be used with a 2 inch pipe ? Dryer vents are 4 inch, and even though the brush has a somewhat flexible head, I wonder if it can be used effectively for 2 inch pipe.

[fishee]

I believe there's a 2-inch version on Amazon but you can also use the smaller brush in the kit I show for 2-inch pipe

[ccokeman]

I back wash with a shop vac in blow mode. Block the extra space with a wet towel and hold it in place until I get air out of the bottom drain. Seems to keep mine clear. Should be less effort and or clogs now that the 60 foot River birch I had no longer hangs over the pond.