yep use 4200. If this is a live well fill pump that does not recycle the water but draws from outside the hull then make sure you dont go nuts on the plastic nut as it will strip realy easy so tighten it then let the 4200 take care of the sealing (test fit all parts before you apply 4200 as there nothing worse than finding the pump has to be removed to put the elbow fitting on after you have sealed it in)