APEX DOS loses prime

dwfain

Community Member
View Badges
Joined
Sep 18, 2020
Messages
96
Reaction score
40
Location
Benton
Rating - 0%
0   0   0
Anyone else have the APEX DOS lose prime? I am dosing RedSea ALK and CA and both lose the prime on all three of my systems. I drilled a small hole in each cap to keep the bottle from collapsing, could that be the reason.
 

SuncrestReef

That Apex guy
View Badges
Joined
Jan 18, 2018
Messages
4,214
Reaction score
9,212
Location
Oregon
Rating - 0%
0   0   0
This is usually caused by a bad connection where the tubing meets the DOS. I always heat the tubing in a cup of near-boiling water to soften it before connecting to the compression fitting for an air-tight seal. Works great for me.
 

Hairyteeth

Well-Known Member
View Badges
Joined
Jun 5, 2020
Messages
644
Reaction score
713
Rating - 0%
0   0   0
Same as above loose fitting on the dos between connection of hose and heads
 

TexanCanuck

Active Member
View Badges
Joined
Feb 10, 2021
Messages
277
Reaction score
259
Location
Dallas, TX
Rating - 0%
0   0   0
The DOS pumps are peristaltic pumps and do not require priming ... as long as they have air-tight connections between the suction side of the pump and the fluid you are pumping they will draw fluid!

Like the previous posters, I strongly suspect the issue is in your tubing connections ... either where it connects to the suction side of the pump, or where it connects to your reservoir.

Personally, I find the tubing that comes with the DOS unit to be highly prone to this problem. Instead, I recommend using a silicon-based tubing of the same dimensions ... solves the problem every time!

Here's what I use:

 
OP
OP
D

dwfain

Community Member
View Badges
Joined
Sep 18, 2020
Messages
96
Reaction score
40
Location
Benton
Rating - 0%
0   0   0
Thanks, order some new tubing. Anyone seen or had experience with the adapter that converts these fittings to the push to connect fittings for more rigid hoses? I've seen them somewhere on R2R but cannot find them now.
 

Hairyteeth

Well-Known Member
View Badges
Joined
Jun 5, 2020
Messages
644
Reaction score
713
Rating - 0%
0   0   0
… no but I saw this thread back up and had a second add on thought, I would keep an extra dos head on stock, I had a leaky one that I over tightened trying to fix, and ruined, ultimately replacing the head/ connections was what fixed it. In This case it was me human error but was nice I had an extra!
 

homer1475

Figuring out the hobby one coral at a time.
View Badges
Joined
Apr 24, 2018
Messages
11,677
Reaction score
18,659
Location
Way upstate NY
Rating - 0%
0   0   0
Never went the push fit fitting route.

I just heated up the end of the RO/DI line, pushed onto the stock connector, cinched up the nut. been working that way for the last 3 years. I never loose prime.
 

TexanCanuck

Active Member
View Badges
Joined
Feb 10, 2021
Messages
277
Reaction score
259
Location
Dallas, TX
Rating - 0%
0   0   0
I've seen a few photos here on R2R showing push-to-connect fittings on the DOS ... but I'm not sure it's worth the effort.

Here's my thinking:
1) once you install the tubing, you are likely to leave it in place for a long period of time. In three years I've never had to remove my tubing ... so I don't see the benefit of the push-to-connect fittings
2) these fittings will add a second leak path for air ... using the provided fittings there is only 1 place for air to get in ... once you add the push-to-connect fittings there are now two (between the pump head and the fitting, and then between the fitting and the tubing)

Bottom line ... it's neat to look at but not sure there is a functional reason for using push-to-connect fittings on the DOS
 

biecacka

Valuable Member
View Badges
Joined
Jan 1, 2012
Messages
2,304
Reaction score
2,112
Location
columbus ohio
Rating - 0%
0   0   0
So I have a DOS that loses prime as well. I have push-to-connect fittings. I bought it used and it came that way, I’ve used it as such for years, but a few weeks ago it started acting up and now it doesn’t move any water. Any ideas??

corey
 

A worm with high fashion and practical utility: Have you ever kept feather dusters in your reef aquarium?

  • I currently have feather dusters in my tank.

    Votes: 64 36.8%
  • Not currently, but I have had feather dusters in my tank in the past.

    Votes: 59 33.9%
  • I have not had feather dusters, but I hope to in the future.

    Votes: 25 14.4%
  • I have no plans to have feather dusters in my tank.

    Votes: 26 14.9%
  • Other.

    Votes: 0 0.0%
Back
Top