The Dosatron D400 is the largest injector in the MegaFlo line, delivering water-powered proportional dosing at up to 400 GPM through a 4 in connection. It uses Dosatron's patented Diversion Technology, which routes a measured portion of the main flow through the dosing motor rather than the full stream, allowing very high throughput without a matching pressure penalty. No electricity, no metering pump, no batch tanks.With a 110 to 400 GPM working range, the D400 is built to dose an entire commercial site from a single point. It is offered across several dilution ranges and seal materials so the unit can be matched to both the required injection ratio and the chemistry being dosed.Available Options 0.1-0.5% (1:1000-1:200) 4 in Viton (FKM) Seals - No Bypass [D400MZ05VFII] 0.02-0.2% (1:5000-1:500) 4 in Viton (FKM) Seals - No Bypass [D400MZ02VFII] 0.003-0.02% (1:30000-1:5000) 4 in Kalrez (FFKM) Seals - No Bypass [D400MZ30000VFIIK] Specifications Flow range: 110 to 400 GPM Operating pressure: 7.25 to 116 psi Connection: 4 in Dilution ranges: 1:30000-1:5000, 1:5000-1:500, and 1:1000-1:200 Seal materials: Viton (FKM) and Kalrez (FFKM) Dose scale: percentage and ratio (HORT); union not included Key Features Water-powered proportional dosing, no electricity required Patented Diversion Technology for high flow without full-stream restriction Externally adjustable injection rate Dosing accuracy holds through supply pressure and flow variation Doses a whole site from a single injection point Field-serviceable; seal and rebuild kits available HORT vs Hydro VersionsThis listing covers the HORT (horticulture) build. Compared to the Hydro (HY) build of the same injector, the dose setting is marked in percentage and ratio rather than ml/gal, no union is included, and no bypass is fitted. If you need to flush clear water without pulling the unit, plumb an external bypass loop around it.Seal SelectionAfter dilution range, seal material is the most important choice you make. The seal is the only part of the injector in constant contact with undiluted concentrate, and running the wrong elastomer is the single most common cause of early injector failure. Viton (FKM) - the general-purpose default. Suited to soluble fertilizers, micronutrients, pH-down acids, wetting agents, and most neutral to mildly acidic feeds. Aflas - for alkaline chemistry. Specify for pH-up, potassium hydroxide, liquid lime, carbonates, and hypochlorite sanitizers, which swell and harden Viton over time. Kalrez (FFKM) - the broadest chemical resistance available. Specify for peracetic acid (PAA), hydrogen peroxide blends, chlorine dioxide, and strong oxidizers such as ZeroTol and SaniDate, or where one unit has to run mixed chemistries. If a single injector will see more than one chemistry, specify to the most aggressive of them. Replacement seal kits and full rebuild kits are stocked for every model listed here.Service and MaintenanceThese injectors are field-serviceable and designed to be rebuilt rather than replaced. Routine service is a seal kit; a full rebuild kit restores the motor and piston assembly. Install a strainer ahead of the unit and flush after dosing aggressive chemistry to get full service life.Ideal Applications Whole-site commercial fertigation Large irrigation mains and nurseries Industrial water treatment Peracetic-acid and oxidizer injection (Kalrez)
