I mean it’s “ok”, it depends on the level of success you are trying to achieve I guess. Full arm gloves are recommended for many different reasons, lots of bad stuff in our tanks, they are bulky though so a lot of reefers don’t use them. If I’m going in my tank without gloves I plan it out and wash my whole arms with dawn, then water, then over the next hour wash 3 more times with just water. Even after doing that I still get a layer of sludge in my sump that appears after I get in the tank, it goes away after a few hours, but it’s still “in there”. If I go on vacation I notice my tank looks much much better when I get home. The only difference is no one sticking their arms/hands in the tank. So i’d say it’s maters quite a bit.