About Y-axis scale in amCharts - amcharts

Question

I am facing problem with scale on vertical axis like 2,4,6,8,10 etc or 5,10,15,20. I have achieved this on one axis (name Iron in ppm) but how to achieve this on second y-axis?
var chart = AmCharts.makeChart("chartdiv", {
"type": "serial",
"theme": "light",
"id": "SweepGraph",
"legend": {
"marginTop": 150,
"useGraphSettings": true
},
"synchronizeGrid": synchronizeGridFlag,
"dataProvider": SortedChartData,
"valueAxes": [{
"id": "BaseNumber",
"axisColor": "#0000ff",
"axisThickness": 2,
"axisAlpha": 1,
"position": "right",
"title": "BaseNumber in mgKOH/g",
"minimum" : BaseNumberMinimum,
"maximum": BaseNumberMaximum,
"autoGridCount": false,
"gridCount": 100,
"synchronizationMultiplier": ironLabelFrequency,
"strictMinMax": true,
//"synchronizationMultiplier": BaseNumberLabelFrequency
}, {
"id": "Iron",
"maximum": IronMaximum,
"minimum": IronMinimum,
"minMaxMultiplier": 0,
"precision": 0,
"synchronizationMultiplier": ironLabelFrequency,
"synchronizeWith": "BaseNumber",
"strictMinMax": true,
"axisAlpha": 1,
"axisColor": "#ff0000",
"axisThickness": 2,
"gridCount": 100,
"gridThickness": 0,
"minHorizontalGap": 0,
"minVerticalGap": 0,
"title": "Iron in ppm"
}],
"graphs": AmCharts.parseJSON(graphData),
"chartScrollbar": {},
"chartCursor": {
"cursorPosition": "pointer",
"oneBalloonOnly": true,
"valueZoomable":true
},
"guides":GlobalSweepGuides,
"categoryField": "FeedRate",
"categoryAxis": {
"gridPosition": "start",
"title": "ACC Value in (g/Kw/h)/(%wt)",
"axisColor": "#DADADA",
"minorGridEnabled": true,
"autoGridCount": false,
"gridCount": 12
},
"export": {
"enabled": true,
"menu": [],
"libs": {
"path": "http://www.amcharts.com/lib/3/plugins/export/libs/"
},
"position": "bottom-right"
}
});
Here is jsFiddle url:https://jsfiddle.net/HARSHAD557/jgz289fw/
Please solve this problem.