The highest selling quality German built doser on the market at $399 with 2 year warranty and known to last and last and last and........ LAST.
For an extra $100 to the nearest Eastern offing why even consider the risk? Buy once buy quality.
We get many requests for the link of this review of the GHL Dosing system so here it is again
http://www.mrsaltwatertank.com/the-g...oser-reviewed/