90 gallon display/30g sump
SWC 160
Lots of Seachem Matrix (not carbon)
100 lbs of live rock roughly
7-8 small fish
MaxCap 180
Water Changes throughout this was 20% every 1-2 weeks.
I wanted to share with everyone my recent bout with Dino's.
So....
My Nitrates were finally down to <1ppm and phosphates ~0.04. My tank was previously overstocked and I had been running biopellets to help with the nutrients. However my PH was constantly low ~7.8 - barely ever making it over 8.0. My organics in my tank were high (obviously since the presence of cyano) and my corals weren't happy. I decided to add Rox Carbon (never ran GAC on this tank). After 24 hours of Rox carbon my tank started to look great - PH started to go into the 8.1/8.2 range as well. My Monti's appeared the worse and they started to actually repair themselves (encrusting monti's had tissue that receded in the middle of them) and color up. Of course the Rox carbon was a temporary fix as it exhausts in a short amount of time.
Right before I added Rox I removed a medium size hippo tang (4-5 inches) and a couple of smaller fish to help with lowering my organics. At this point I knew I just had to play the waiting game for things to get back to normal. (Had low Nitrates/Phosphate before this, but knew my DOC's were possibly a cause to my problems).
My T5's were all a year old (8x54w Tek Light) and I decided to replace 4 bulbs (out of 8). 2 Coral Plus, 1 Aquablue special and 1 Pure Actinic. This was a drastic coloration change as I replaced 1 fiji pink and 3 blue plus.
Shortly after, my Corals were getting better and cyano was manageable, but I started to notice "brown algae" growing on the upper back glass, powerheads, frag racks but not really on the bare bottom or the rocks. My nitrates were < 1 (0.2) and my phosphate at around 0.08. My first reaction was that my new T5's and their spectrum (much warmer) were the cause, so I cut back the amount of time I was running the two Coral+'s as well as raised my light a few more inches and it at first seemed to help slow the growth but my glass and frag racks were still getting covered. I had to clean my front,side and black glass a lot.
Once I realized it wasn't getting better and that my cyano was actually starting to get worse also (GAC most likely exhausted - this was the 30 day point), I knew GAC (Rox) wasn't going to compensate (unless I constantly changed it out) and that something else was the matter. I went ahead and replaced my GAC with a fresh 2 cups) and I decided to take my biopellets offline, as I figured at this point with the smaller amount of fish and their size that BP is probably overkill plus it could be increasing the amount of "ogranics" in the tank. After taking that offline my PH began to hang out around 8.3 with the lights on. Dino's were still a problem at this point, Cyano getting a bit better but still existent. I had also been dosing trace elements which I decided to stop.
So after a month and a half of all this I can see my corals are doing great but there was cyano and dino's present still. Just the corals on the frag racks were getting dino's growing on them.... At this point, I hadn't lost a coral so I never actually went into panic mode. I began to wonder, hmmm what else could be the matter, the dino's and cyano were not completely out of control, but ugly and annoying.
After a few days of just waiting. My wife comes to me and says, "ugh, the stupid water jugs take forever to fill up" (we make RO water for drinking). Use to take 30-45 minutes to fill up (5 gallon water jugs) and now its taking 1.5 to 2 hours. I think to myself, "uh, yeah that's bad". I go and look at my MaxCap 180 and notice my PSI is at 20'ish and should normally be up near 60psi. I bypass my sediment cartridge first and no luck. I bypass my carbon block and BAM the PSI goes back to normal. I check my TDS on my RO and DI's cartridges and I was pushing 4-5ppm TDS into my (RODI) reservoir which I used for my ATO buckets and my water change water.
Replaced all my filters for my Maxcap (mid March) accept for my RO membranes. Cleaned my ATO buckets as well as my Brute trashcan reservoir.
Anyhow, since then my dino's are just about gone (definitely not progressing) after a few water changes and scrubbing.
One thing I noticed was I didn't have any coraline algae growing for quite some time. Since then I am starting to see it in new places.