Floating pickup for finished bio tank - design / tube type?

[julianf]

I purchased this, off ebay, last week -



Ive never looked at these plastic tanks before.  Kind of surprised that theyre not more air-tight around the filler (i know they have to be vented, but the filler is just a flap over a hole?)

Anyhow, that aside, it has a single, i think, 1/2 or 3/4 port at the base, and then some fittings at the top.


I dont want to drag crud out of the lower port, so i either need to fix a tube down the inside, to, say, 1/4 from the bottom, or make one of the floating pickups.


I have an old toilet ball float, so i thought i could use that, chain (or wire tie) it to a heavy hosetail / fitting combination, and then pipe that up to one of the ports in the top of the tank.


But im unsure what hose to use.  Everything seems to go hard with bio, which will stop the device working.  Suggestions?

[julianf]

...im also thinking that the construction of the tank (the bridges between the walls) might cause me some bother (with things getting caught up)

Maybe id do better with a fixed tube, and never use the lowest few hundred liters?

[Tony]

For in-tank tubing hep2o or equivalent, the stuff I have has survived hot bio for many years.

[julianf]

isnt hep2o like PEX - ie fairly ridged?

[Julian]

I used a float from a ball cock, attached to a couple of links of chain which in turn was attached to a piece of corrugated polythene pipe off one of those siphon pumps with the red concertina bit.

Cost pennies and it's worked well for several years.

[Tony]

isnt hep2o like PEX - ie fairly ridged?

Yes, I was thinking you wanted to make something like this with compression fittings:

http://www.biopowered.co.uk/wiki/Top_skimming_fueling_tank

[julesandtash]

I made one of those floating pickups for my tank with pex pipe and push fit fittings. For the one at the bottom of the tank which pivots, I just took the O ring out which allowed the pipe to rotate in the fitting. Yes there will be slight leakage but it is always submerged in the fuel and 99.9% of the fuel will be sucked via the floating end of the pivoting pipe.

Unfortunately that tank has two sections which run right across the tank so my type of floating pickup would not work.

What about that silicon hose you used to have on your external boiler. That seemed to stay extremely flexible even when used for biodiesel.

As for the lid, mine is exactly the same and works perfectly fine, never seems to allow any water into the tank even in really bad weather

[Julian]

I wasn't convinced my description of my pickup from memory was correct, so I fished it out of the tank and took a photo earlier this afternoon. 

For some reason I can't log on to my web space, so I've attached it to this post instead.

In case the photo's not clear, it's ball float, bolt (still ¼" Whitworth I think) chain link, little homemade linky bit soldered to a gauze with a soldered cap (can't remember where I got it from), attached to the corrugated poly pipe with a hose clip.

Hope it's useful.