Neptune Apex system Dos

[user17482]

Hi everyone, I've had a few problems with my neptune dos. It's second hand and seems to be fairly old, I was wondering if it is probably time to replace the heads of the doser. It's not properly working at the moment I tried to have the lines at about 2 feet from the inlet of the doser and no liquid came out. When the lines were submerged and I tried calibrating it for probably 5 minutes. Since no liquid came out I decided to try it with no lines and see if that was the issue. So I held a cup of water on the inlet of the doser and liquid did enter and leave the doser. I then flushed the lines with air and water tried it again and nothing happened. I've done lots of research on this and have come to the conclusion it's probably time to replace the dosing heads as the last owner didn't drain the lines or replace the heads of 2 years. Let me know I would love some second opinions!

( sorry the images uploaded weird )

 

[Flux Capacitor]

It can’t hurt to replace the heads. Have you removed the John guest mods for the ro tubing from the heads? They could be pulling air if there’s not a tight seal. Before you buy new heads try to take those off, and either us some Teflon tape and reinstall them, or just put a tube on the gray fitting that’s underneath.

 

[BryanM]

I do not know what a john guest mod is....

But I had a line with a hole, and if you get air coming in, air moves way easier than fluids. Completely failed due to a hole in the line.

 

[braaap]

I do not know what a john guest mod is....

But I had a line with a hole, and if you get air coming in, air moves way easier than fluids. Completely failed due to a hole in the line.

Those fittings on the heads. Those do not come stock. It is a mod to be able to use RO tubing. They notoriously suck in air as they don't fit properly. You really have to wrench them down extremely tight. That is likely your issue. I had a pair of DOS for 3 years and never replaced the heads. They were dosing 100s of ML each per day. I don't remember the exact amount.

 

[user17482]

So the person I purchased it from gave me the normal grey fitting as well and I gave those a shot and it worked! the Ro type of fitting wasn't exactly working right and now replacing it with the grey fitting worked great! Thank you so much, you just saved me 100 dollars!

 

[user17482]

Those fittings on the heads. Those do not come stock. It is a mod to be able to use RO tubing. They notoriously suck in air as they don't fit properly. You really have to wrench them down extremely tight. That is likely your issue. I had a pair of DOS for 3 years and never replaced the heads. They were dosing 100s of ML each per day. I don't remember the exact amount.

Yes thank you! that was most likely the issue with them.

 

[braaap]

Yes thank you! that was most likely the issue with them.

If you use heavy pipe tape and tighten them extremely tight they usually work. I used them on my pair for years with no issues. That said the stock tubing is likely far more reliable but it isn't exactly cheap.

 

[areefer01]

Also worth noting that it doesn't hurt to have a pair of spare heads on-hand. Sometimes stock is low and they are hard to find. They are a wear and tear item longevity of course will vary by each hobbyist use case.

 

[user17482]

Also worth noting that it doesn't hurt to have a pair of spare heads on-hand. Sometimes stock is low and they are hard to find. They are a wear and tear item longevity of course will vary by each hobbyist use case.

Thanks for letting me know!