I've been a vegetarian most of my life. I do not take supplements or vitamins. I get plenty of B12/iron through natural and fortified (synthetic) food sources.
I'm a little confused that you would think you are deficient since you are a pescetarian, take a multivitamin and said your log shows you get enough. I would check your food logs to make sure you are recording your B12/iron properly, especially your custom foods.
Cheeses (swiss, mozz, feta, parm, etc.) milk, soymilk, whey, whole eggs, yogurt, yeast extract, tofu and fish/shell fish are good sources for B12.
Seeds (sunflower, pumpkin, sesame, etc.) Dried fruit (raisins, apricot, apples, figs etc.) Beans, tofu, cocoa powder, dark chocolate and shell fish a good sources for iron.
Are you getting enough vitamin A? TBH, I don't eat 1/2 of the examples I listed but I still show no deficiencies in those vitamin levels. I do get a lot of vitamin A (best sources are fruits and veggies) which allows my body to absorb iron easily.
"Just Do It"