Hello! (Tom, you might have just the recipe for this one...)
I apologize for the length, but the info might be necessary for the plan of correction...
First of all, I've been rereading Delbeek & Sprung Vol I and various articles Tom Wyatt's written in the posts here that I've collected and printed over time....
Over the past 6 weeks, conditions in both large tanks have improved, but I'm at a point where I'm afraid I'll run into trouble and I still can't get it right. Here are the current readings:
120G Reef w/20G sump, macroalgae growing in the sump, sump light on at night. 2 175w 10,000K MH with 2 110w VHO actinics
2 Maxi 1200's, vertical spray bar down the center, horizontal spraybar across the bottom, GenX Mak4 return pump, Berlin TriplePass skimmer in sump, 4-5" sandbed w/plenum, tons of LR. 3-1/2 yrs old. 7 fish, 10 Hr photo period
Leathers are thriving and growing WELL. Frogspawn has improved tremendously in past 6 wks, added Galaxia month ago and it's thriving well. One sps "cup" is doing well - added it in early April. Can't keep other sps's healthy or alive, haven't tried more than two, lost both.
Chemistry - as of afternoon today, 5/12/02:
(All test kits are Salifert, Kent Marine 3-stage RO unit)
pH: 8.02 (never gets higher) Using calibrated Pinpoint Probe.
Calcium: ~390 (was ~340 a month ago, used to be 475 ages ago)
ALK: 5.0 / 13.6dKH (used to be 4.34 / 12.2 fairly consistently)
PO4: 1.0; or .33 phosphate/phosphor (which is the orthophosphate reading??)
Nitrites and Ammonia: 0
I've used Kalkwasser, B-Ionics 1 & 2, and Aragomight on alternating times to try to get the calcium and pH up. I added the Maxi 1200's at opposite ends aimed at the surface to get more surface movement, and we've done 15-20 gal water changes every 2-3 weeks for the past couple of months. There is currently no significant hair algae or other algae problem.
I'm afraid I'm going to get the alkalinity up too high while trying to get the calcium up and the pH up some.
Our auto-topoff water has always just been RO water, nothing added. I'm thinking I should add Kalkwater to the topoff? Can I add aragomight at the same time, or just one product at a time? I've been adding 35cc's B-Ionic 1 & 2 each after the lights go out or first thing in the morning.
The 125G FOWLR tank (>2 yrs old) has the same sand/plenum/return-pump/sump/skimmer/pwrhead specs, with PC smartlight lighting and auto-topoff, RO water w/nothing added,
7 fish, and here's its chemistry:
Calcium: 500+ (!)
pH: 7.82 (up from 7.6-7.7 a couple months ago)
ALK: 3.7-meq/l / 10.4-dKH
Nitrates: 100 (!) (down from 100+, and feeding MUCH LESS!)
also, never have had an algae problem in this tank...
PO4: slightly >1.0
Nitrites and Ammonia: 0
I only add the B-ionics to this tank now since the calcium jumped up so high. (35cc ea every day or every other day)
Have done 15-20 gal water changes every two weeks for past couple months and added plants to the sump today.
Thanks VERY MUCH in advance!