To UV/Diatom Filter, or Not to Filter?

I am hoping to get some feedback about whether to add a UV or diatom filter following my first bout with green water algae bloom! Replaced my carbon with purigen about 2 weeks ago, and just 2 days ago I get cloudy water (maybe relted, probably not).

I have a 46 gallon bowfront african cichlid, planted tank with the following specs:

Nitrates: 20-30ppm
Nitrites:0
Ammonia:0
pH:8.2

Coralife 2X96w 50/50 and 6700 running 8 hrs/day

Dosing Seachem Flourish, Nitrogen, Phosphate, and Excel once a week.

Two AC70 filters: Sponge, Purigen (in one), Filter Floss, BioMax, and crushed coral (in one). NO carbon.

10-20% Water changes weekly.

So what do you guys and gals think? Do I need to add a UV or diatom filter to prevent another bloom? Or just deal with them as they come? If yes, do any work without canister or similar filter?

Doing weekly water changes, about 10-20%

Yes, I use Malawi Buffer. I didn't think about the extra phosphate in it!

Does the diatom filter "protect" against green water as much as UV filters?

Thanks for your help!!!

Since I never had a problem until two days ago, I never thought I was using too much light since the plants are doing well.

I like the UV filter idea because it easy to use - turn on when needed and off when not - but dont like having to put in a power head for it.

And I like the diatom filter but don't like the "hassle" of recharging each time I turn it off.

Any thoughts?

Anubias, lots of jungle val, and something unknown!