Why is BRS alk doing this to my tank?

[MizTanks]

Ever since I started using the BRS 2 part alk I've been getting this brown rusty substance on my sand bed. How I know that it's the alk part is because I stopped using it for about 5 days and the stuff vanished. Then I started dosing again 2 days ago and it's coming back.
I'm dosing 5ml daily, at night after lights out. Adding it directly into the high flow of my mp10. I will actually turn the flow up while dosing.

[dputt88]

those are diatoms i dont know why brs alk would do this.

[slapshot]

By turnin the flow up your POSSIBLY stirin more crap up and POSSIBLY causin a small cycle or atleast pushin more crap out which is POSSIBLY the real cause.... not the actual BRS mix as it shouldn't have anythin that could cause this issue

If you seriously think its BRS's issue.... An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com .... this is what I do and its much cheaper. I paid like $15 for a 40 lb bucket of ice melter (which I have barely put a dent in with a 180 lol) and bakin soda isn't much!

+1 Costco has big bags of baking soda for $4.

[BlackGrandPrix]

More than likely it's an impurity in their mix that is feeding the diatoms.

[MizTanks]

Ok well I wont turn the flow up anymore and see if that changes anything. But I do believe this started before I decided to turn the flow up during dosing, because it was this issue that caused me to turn the flow up in the first place.