Fluconazole and Lanthanum chloride treatment

[ReeferDave01]

Within past 3 months I’ve had issues with GHA. It’s gone progressively worse since I added T5 to my LED. T5’s only run at peak 3 hrs. Ive shut them off since and have reduced LED intensity (Marine Orbit Pro) but GHA has been slowly spreading. It’s not huge but definitely annoying. I have hermits & snails bunch of tangs but still persists. My tank is 220 gallon main tank, 60 gallon aux tank (smaller fish), and about 80 gallon sump all piped together. I have an Octopus skimmer, UV runs in sump 12 hrs day, ozone 3 days a week for an hour and 3 filter socks that I change 2x a week. I also have 3 gallon fuge attached to Aux tank as overflow runs opposite cycle. Also note I have zero GHA in aux tank that has much less intense light that is mostly white/blue.

My most recent parameters have been (checked thru Hana/Apex) – temp 78, pH 7.9-8, Salt 35, ORP 328, Alk 10.3, Ca 464, Mg over 1500, Phos 0.09 (tank ave has been 0.226 most of time Phos runs 0.10 – 0.20). My tank is mostly FOWLR with about 30 fish, some corals. I feed about 5 cubes a day. Oh and I make water with 5 stage RODI filter.

Im thinking of doing a 2 step method and wanted to see if anyone has any success or what the thoughts are.

Step 1 – Fluconazole treatment. This will rid of GHA that’s there now. I believe 20 mg per 1 gallon is advisable treatment. Run this once for 3 weeks. Once done, go on to Step 2 below.

Step 2 – Lanthanum chloride treatment & maintenance with low dosage to keep Phos down. I was going to run 5 ml for my tank, check results and then do this every 1-2 months or if Phos go above 0.03. Drip into 10 micron sock.

Has anyone tried this, any advise or anything I should be concerned with? Thanks

 

[ReeferDave01]

Pics attached

 

[ReefTeacher]

I just recently did what you describe, but in the opposite order. I was trying to battle the HA with Lanthanum chloride, and my phosphate was quite low, 0.3-0.2 ppm per Hanna, but the HA still persisted. So I tried fluconazole. It worked great and no detrimental effects on any of the Corals (both softies and SPS). I have not dosed LaCl2 since because my phosphates remain in the same low range. I did see a raise in nitrates, however. It has only been 4 weeks but things look good.

 

[Randy Holmes-Farley]

I just recently did what you describe, but in the opposite order. I was trying to battle the HA with Lanthanum chloride, and my phosphate was quite low, 0.3-0.2 ppm per Hanna, but the HA still persisted. So I tried fluconazole. It worked great and no detrimental effects on any of the Corals (both softies and SPS). I have not dosed LaCl2 since because my phosphates remain in the same low range. I did see a raise in nitrates, however. It has only been 4 weeks but things look good.

0.2-0.3 ppm phosphate is not "low", and is not nearly low enough to deter algae growth.

 

[ReeferDave01]

@Randy Holmes-Farley - in my 2 step process I listed above. Do you recommend doing step 1 then step 2, or doing step 2 then step 1? Any thoughts?

 

[Randy Holmes-Farley]

@Randy Holmes-Farley - in my 2 step process I listed above. Do you recommend doing step 1 then step 2, or doing step 2 then step 1? Any thoughts?

One then 2, as you suggested. You want to take out the phosphate released from the dead algae.

 

[ReefTeacher]

0.2-0.3 ppm phosphate is not "low", and is not nearly low enough to deter algae growth.

Randy, thanks for catching my error! it was 0.03-0.02 ppm as per the Hanna tester.

 

[Randy Holmes-Farley]

Randy, thanks for catching my error! it was 0.03-0.02 ppm as per the Hanna tester.

While that is a good target, it isn't necessarily low enough to prevent algae growth. It would just barely begin to deter phytoplankton growth.

Phosphate In The Reef Aquarium
https://www.reef2reef.com/blog/?p=3184

At concentrations below about 0.03 ppm, the growth rate of many phytoplankton species depends on the phosphate concentration (assuming that something else, such as nitrogen or iron, is not limiting their growth). Above this level, many organisms’ growth rate is independent of phosphate concentration.1 Consequently, to deter algal growth by controlling phosphate, aquarists need to keep the phosphate levels quite low.