Pre-filter For FX6 - Will It Work?

HI luvly ppl -    HNY ( sorry, bit late ).. so, perhaps you've guessed that I've watched most of Pond Gurus' filter revues.. impressive and useful stuff - I've even seen some avid US professional aquarists and hobbyists on Youtube using his Biohome Ultimate media, but yet to hear anyone confirm his 'close to zero' nitrate claim.. I can't afford the £75+ it wud cost to fill my 3 baskets ( about 5kg )with Ultimate - which is basically sintered glass much like natural white pumice - except man-made.. so I took the 'poor mans' route and bought 10kg of pumice for £20..and filled 2 baskets already.  some of you may remember my posts from 6 mths back when I started my 350L cichlid tank ( all 2nd-hand stuff inc. the filter ) so now, the tank is not overstocked, but some  are close to adult size, plus 5-yesr old 'stripey Joe' - the Frontosa - laid back as ever, so quite a bio load..     Now, I'm thinkin' the FX6 is overloaded wi' sponges and plan to fill 2 of the outer trays with more bio media, so I bought a tiny 2L SunSun HW602B pre-filter, comes complete with course / med / fine sponges.. got the necessary fittings, and hose arriving tomorrow .. getting to the nitty-gritty - I plan to fit the tank suction hose to suction side of SS, then SS outlet to FX6 inlet, FX6 outlet back to tank. The only pump involved will be the FX pump ( rated at 3500 l/h with mt canister, so perhaps 1500 l/h when set up )..my question - the FX6 inlet / outlet hoses are 22mm ID, with shut-off ball valves, but no 'variable control' on the pump.. the SS inlet / outlet are both 12mm ID, so surface area less than 1/3 that of the FX6.. I believe I cud reduce the pump outlet rate by partly closing the outlet valve ( tho' never tried it ) so wondering if safe to run this setup without the pump overheating ?     course, other option is get a bigger pre-filter canister wi' same size hoses..mebbe later.. thks any advice..

I haven’t used this type of filter before however the idea of part closing the plumbing valve to reduce flow will only add more running pressure to the valve, pump unit and the hoses which could reduce the life of the motor etc, cause an Over load electrically which could trip it out. The valve may also fail or pop shut or fully open which isn’t ideal.

Not tying to put you off but from a plumbing background, I wouldn’t treat it like you would a tap. The water coming into the filter will need to be unrestricted to enable the water to flow through unrestricted.

Congratulations on your new arrivals.