What role do pods play in the reef

[reefman316]

The more I look in my tank the more I'm starting to notice all the little creatures in the gravel and crawling on the live rock.I've found two of the creatures in a magazine of mine,they are Harpacticoid copepods,and Gnathopods.What I want to know is what type of role do they play in the reef tank other than being scavengers?Any thoughts or input will help me greatly because I feel my tank is ready for fish when I can come up with some cash flow.
20 gallon long glass tank
1 fluval 204 canister filter
1 aquaclear 200 hang on the back filter
1 aquaclear 150 hang on the back filter
2 powerheads for circulation
1 standard heater
15 lbs reef sand(arogonite)
5 lbs live sand
20 lbs tonga branch live rock
3 turbo snails
3 small hermit crabs
1 mushroom polyp
2 other small sof corals that I can't identify yet

 

[adrian]

They are very low in the food chain, they feed on detritus and algae and are vital to a healthy reef, enjoy seeing them while you can, once you start introducing fish you wont see many