Air in DOS line

[Jon M.]

Can anyone help here? Brand new heads. Brand new lines. No air in line coming from sump but air on other side of head to waste drain. Seems gravity is the culprit?

 

[Clownfishy]

Interested to know the answer to this as my DOS has done the same since day 1.

 

[Fiesty]

Mine also. Following along.

 

[Waters]

Both of mine have air in the lines, all the time. It is really annoying lol. Doesn't seem to affect dosing amounts though (I have checked that). The only thing that seemed to work for me is to continuously replace the tubing with Neptune branded airline....like every month....which I refuse to do. I ended up removing the existing connection fittings and using RO/DI line which worked for a little bit but I am back to the same air in the tubing. I have even replaced all the internal parts with no luck. I am not sure it is possible to keep air out of them.

 

[BetURWrasse]

get some of these, best thing I ever did. use either the liquid or just the tape thread sealer and some 1/4 OD polyethylene tubing.

https://www.amazon.com/gp/product/B003YKF256/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

 

[Silver14SS]

get some of these, best thing I ever did. use either the liquid or just the tape thread sealer and some 1/4 OD polyethylene tubing.

https://www.amazon.com/gp/product/B003YKF256/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

I did this as well, no more air issues

 

[Water Dog]

I bought my John Guest adapters on FreshwaterSystems.com as they sell them individually. I also used Plasto Joint Stik on the DOS male threads to ensure a tight leak free seal.

https://www.freshwatersystems.com/p...uY29tIiwgImtsX2NvbXBhbnlfaWQiOiAiSENNdjQ0In0=

https://www.amazon.com/Plasto-Joint...15SA43B1M0541D0J7GQF&qid=1560257785&s=gateway