Red Sea Dosing bottles lose vacuum

[AquaPhilNJ]

The Red Sea reef foundation Alkalinity black bottle has ability to attach dosing tube to the top of the lid, then another tube attached on the bottom, but this setup keeps loosing vacuum; meaning tube (from bottle into doser) has no liquid as the liquid has dropped into bottle. Maybe one or two days it is fine, then suddenly somehow all goes back into bottle. These large air gaps in tubes make it hard to know what i've dosed. I use 4 mm ID / 6 mm OD tubing. I been using same bottles a year and i'm guessing Red Sea still uses these same bottles.

Everyone else has this same issue? I believe tubing is tight against lid and did all I can do; I have a solution, for solution I plan to drill a hole into lid and ignore their attachment on lid. I just wonder if this is common issue with Red Sea bottles.

 

[Ron Reefman]

It sounds like an issue of the dosing pump holding the vacuum. But without seeing it, it's hard to say for sure.

Also, you want to be sure your line from the bottle (reservoir) to the dosing pump doesn't have any air in it when you start it up. An air pocket it the line could release the siphon when it gets to the dosing pump.