Filter for water cooling inlet

[Nemie]

I have had my new boat about five months and last few moves I have made I noticed increase in smoke and felt loss of power, I have done a full oil and oil filter change, but still the smoke and this time temp rise to 100, it normally runs at 90, I pulled over and noticed that my water inlet pipe is just above the leg but it had no filter on it, so I stripped the pipe off and there was small amount of algae inside it cleaned it.

 

Now engine side I put my finger inside and it was blocked with algae but luckily there is a wire mesh built into the system, I got as much out as I could and started the boat and now I was getting a nice flow of water from the exhaust. the engine is a thornycroft 108.

 

So now can anyone help me as to what filter I can put on the end of a hanging in water pipe to prevent this from keep happening.

[Dalslandia]

https://www.bing.com/images/search?q=sjoevattenfilter&qpvt=sjoevattenfilter&qpvt=sjoevattenfilter&qpvt=sjoevattenfilter&FORM=IGRE