yah sorry if my reply came off as snarky. The tone in my head when I wrote it sounded completely different from the tone that came across when I just re-read it now.

I still stand by the assertion that I am suspicious of products like MB7 for all the reasons I've already listed, but a) I've never tried it and b) I was totally wrong when I said I didn't think any bacteria could still be alive in those bottles. That would have been a true statement for nitrifiers like Nitrosomonas and Nitrobacter bacteria, but not for the kinds of heterotrophs that will be consuming biopellets. Whether or not there actually is any bacteria in those bottles, or whether or not they always work the way their producers claim in every application is something that I think still has a lot of room for snake oilery, but there's enough people who swear by them (such as yourself) for me to think it's worth looking in to. At some point we have to trust that people who make the products we use know what they're doing, but so many of those products have biologically meaningless fluff phrases on them like "maintains optimal enzyme balance" that the skeptic in me is constantly wanting to call foul. It doesn't mean they don't work obviously, but still. If this strategy works, I'll obviously continue to use MB7, for as long as it seems to work, even if I'll never be able to say for sure that what I think is happening is actually what's going on.

As for my theory of cyano - well it's changing as I learn more. It's still probably not even close to right, but the only thing I do know is that simply telling someone to reduce their nutrients, be that through more water changes, heavier skimming, or less feeding can result in some very confused and frustrated aquarists. There's way more to it than that, and I agree that phosphate isn't necessarily the whole story, but it's certainly part of it. It's just that when I was reading forums back when I started I came across way too many 1 or 2 sentence statements about the nature of things that were treated as absolutes with no justification behind them. It's why I try and always support what I say with some kind of theory or backup, so that even if I'm wrong, where I'm wrong or how I came to be wrong can be pointed out. It makes for wind baggy posts though.

i used chemiclean as per suggested and its been 3 weeks now i think , havent seen nothing, do have a bit of algae now, i need to change my gfo out again.
after 24 hours i still had some cyano , so i said heck with it and left it another 24 and bam, all gone so far. knock on wood

I used chemiclean without issue, left in tank for a week or so, no more cyano. works for me. I'm blaming old T5 lighting for it showing up in the first place.

what's really surprising is that this time all traces of dinos, which I also had (but in low concentration) have vanished. I've confirmed that they were dinos under a scope, but I didn't think chemiclean had any effectiveness against them?

the chemiclean is so cheap and easy to use not to mention you don't have to dose it. I seem to be able to go months between needing a dose and I have enough in a $30 container to last me many years. i've seen the mb7 mentioned quite often but i prefer dealing with it when it does pop up which is rarely.

Yes, having a theory is better than blindly taking action without any understanding of what you are doing. But as you probably well know, after a theory, comes testing, and properly interpreting the results. And then repeat, and repeat...

In your case, you started MB7 before doing the Chemiclean, which as I said was a total waste (hate to say it so bluntly). The cyano was already well established and being fed by your carbon dosing. Ideally, you are supposed to start the heavy dosage schedule of MB7 for 2 weeks even before carbon dosing. And then gradually increase (bio pellets, vodka or whatever). If you over dose with your carbon, you can be right back to square zero.

And then when you did the Chemiclean you probably wiped out any MB7 bacteria as well as the cyano.

So right now you are at square zero, and how you proceed from this point is most important. Like I said, this is when you need to dose MB7 heavily for 2 weeks. I would even shut down your bio pellet reactor for that time. Because right now it is probably not even working (needs bacteria) effectively anyway, and might just promote again the bad bacteria (like cyano).

Back to the theory and my experience, I have to say MB7 has worked exactly as I expected (and advertised), so I don't think my theory has been far off. What was especially telling for me, is in the past it tried to reappear when I had stopped dosing MB7 (because I was away for a few extended time periods). But after heavy dosage for a week, it would disappear. This actually happened a couple times, and each time I was quickly able to beat it before it got out of hand. But have not seen it for a long time now. Wish I could say the same for GHA and other algae (although I have a theory there, too, and my actions seem to be working with that too, now).

You think the BPs are toast? I debated redirecting the inlet and outlet of the reactor to a bucket of water while I did the treatment but lazy reefer syndrome took over. I really wish I knew what chemiclean was made of so I'd know more about what it's actually doing. It's obviously safe to nitrifiers or it would nuke tanks, but something in it is killing bacteria.

They say on the box that it's specifically not erythromycin succinate, which either means it's not erythromycin at all, or it's just a super sneaky way of saying that it's actually erythromycin estolate or stearate or something like that.

well soylent green is people... so anything's possible.

Don't think they are toast, but am quite sure their effectiveness has been interrupted. What's worse, is they can be producing carbon, but with no or very little beneficial bacteria present, could resurrect the cyano again. It for sure, thrives on carbon dosing.

That's why I say you should suspend the BP's for a couple weeks, while you dose your system with MB7 and get the beneficial bacteria fully seeded. Then introduce the bio pellets slowly again, to be sure nothing gets out of whack again.

Ive done the treatment before and had to do a repeat after the 20% waterchange , it was a skimmerless tank only ran carbon and everything was fine , now I didn't have any sps at the time so I cant comment on the effect on them .