Can I feed this to my clownfish? And other advice.

I have two new perculas that are about an inch and a quarter. I took two out of a school of eight over at the store. I bought marine flakes and new life spectrum pellets but both seem too big for them to eat, although they still eat some of the flakes. So I found these 0.5 mm pellets online. I want something small enough for them to eat and for my damsel not to see, cause everyone knows how much damselfish eat. I'm not allowed to post a link yet so here it is:

Ingredients
Herring Meal, Kelp Meal, Squid Meal, Spirulina, Garlic, Chlorella Algae, Yeast, Yeast Extract, Paprika Oleoresin, DL Methionine, Brewers Dried Yeast, Lecithin, Astaxanthin, Beta Carotene, Canthaxanthin,and vitamins and minerals

Analysis
54% Protein
8% Fat
3% Fiber
10% Moisture

Specs
Sinking Pellet
0.5mm in size

Check out the ingredients and let me know. Also on that matter, two clownfish and a 4 striped damselfish in a 20 gal nano reef fine? He doesn't attack them but he will go by them and sometimes he'll spike up, but still, he can rub right against them and not attack. If anything since I added the clowns the damsel has become less lethargic and more willing to swim around. And judging by the size of the clowns, how old do you think they are? I've already seen one swim to it's side and vibrate which looks like they're pairing up. Thanks, I'm new to this if you haven't noticed but I did a lot of research before jumping into it.