Can three of these be used in a loop with taking much away from flow?

I use three. I also add fiberfill to two of them. One before CPU water block, one before two GPU's (NVLINK) and one at pump discharge (twin D5's in parallel) with activated charcoal. I strongly recommend having one just before each water block if nowhere else. Water blocks have notoriously fine passages that plug readily and are a relative nightmare to clean in comparison to a filter. With three water blocks and 700mm (total) of double thick radiators my pumps put out about 90liters/hour flow at 9psi. I get around 120 without filters at that same pressure. So my setup is probably more "worse case" than most in terms of restriction. As they get plugged pressure goes up to about 9.5 with a corresponding flow drop to about 50. When they clog I am thankful they are in place, otherwise I'd be tearing my PC apart to clean the water blocks. But even at 50 liters/hour, my CPU temp (Ryzen 3960 w/24 cores at 4225Mhz) never exceeds 45c. Again, I have a lot of radiator surface area. This also only happens after I do a flush or mess with the chemistry, change configuration or adjust fittings etc. Otherwise they don't clog that quickly in steady state operation. So, the answer really depends on your setup. Mine handles 3 fine. Two with fiberfill and one with charcoal. No matter what setup you have, put one just before each water block and use fiberfill. As the fiberfill gets pushed down you can gage how much crud its collecting, even if you can't see it. Like lime or calcium. The screen will stop the fiberfill from getting into your system. Nothing you can use in a home PC, without extreme cost (ammonia/Dry Ice/Freon) and effort cools better than pure water. All else will add impurities, reduce flow and has a worse specific heat capacity. If you need a different pump to handle it then the upgrade will be worth it. All it takes is one drop of water on your motherboard/PCIE slot/CPU socket/RAM slot during a block removal/cleaning to destroy your hard work and investment. Always locate your filters with a drain.

Can I use in a loop with cooper and nickel? So, it’ll be stainless steel, cooper and nickel in the same loop with koolance 702

As far as I'm aware you should be fine, do try to avoid aluminum and silver though

Anybody know if this would work well with opeg Pascal fluids? Something like ek fluid or primochill vue?

Probably not, the mesh is somewhat fine and I had clogging issues with a simple colored fluid, I eventually removed it becuase anything at all not fluid itself would be caught and put more pressure than necessary on the pump.

Can this be used with hard tubing petg ????

this part does not have any fittings, it has g1/4" threads to put fittings into. so yes, if you have the appropriate hard-tube fittings for each side, it'll work. However, be wary of using the silver in your custom loop, it might not be the answer you're looking for. I advise doing further research to see if it's the product for you.

G1/4" Inline Filter, Black Chrome

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