i honestly think you need to address your water quality. get that water report from your local water supplier. you may need to switch to RO water (although i'm not sure how that works, i think you need to add minerals back into it? sounds like Crepe may know the procedure there.)
Just tonight, we noticed the diatoms have become ridiculously aggressive now, climbing all over the right bottom corner of the glass and upward, continuing to overtake the ornaments and gravel -- we have to definitely do something. I don't know if it's my tap water at this point, Rachel, or something else, but I will try, once more, the distilled bottled water and more Seachem PhosGuard.
are you keeping nitrates as low as you can to try to starve the algae?
[moderator edit] it -- I didn't want to face it, but it looks like the lack of water changes may be feeding this problem...thus, nitrates may have climbed through the roof (I haven't done a test of the water in some time)...
As I stated earlier in this long thread, I was afraid of doing routine water changes if the problem was stemming from our tap water supply -- my thinking was, if the tap water is contaminated with silicates, this just continues to pump these things into the column of our tank with each change...but then as stated by many, the activity of constantly changing out the tank water may have been enough to combat the diatoms, so I don't know.
are you going through mini-cycles when you change out your filter cartridges?
No.
you can just pop them open and scrape out the carbon when it becomes "used up" and keep using the cartridge. it's really unnecessary to change them out monthly as the instructions suggest.
So, just use the actual cotton floss and that's it?
I know it's unnecessary to keep buying new ones, but I just feel more comfortable doing it; but, I can't believe that
all the beneficial bacteria would be killed off just from thowing out old cartridges or rinsing them off...if that was the case, why would Aqueon (outside of the profit factor) instruct people to do so? I mean, wouldn't this have caused widespread tank crashes on a massive scale already, leading back to the company? The instructions that come with new cartridges for these "QuietFlow" filters state that while cartridges can and should be replaced, the actual "bio bar" and "bio grids" which sit in the filters (they're actually just blue pieces of plastic) are the areas which house all the growing bacteria, and these are not to be rinsed off. So, there must be BB growing somewhere other than just on these cartridge surfaces...
and yes, i've read several places that diatoms will show up anytime during the first year or year and a half. they don't normally stick around as yours have, but popping up within the first year of a tank set up is not unusual.
I didn't know that, and was under the assumption that by 12 months the entire system should be in balance -- my situation even has technicians at Seachem and other companies completely baffled.