Fluconazole and water changes

Tastee · Feb 10, 2019

Hi, I have just treated my tank with Reef Flux to help deal with a GHA issue and would like to hear your thoughts on water changes after the treatment. The standard instructions are to perform a minimum 30% WC 14 days after treatment. What are everyone’s thoughts on the need for this?

My assumption is that the intention of the WC is to reduce Nitrate and Phosphate liberated when the GHA is killed off. I can’t think of any other benefit of a large WC. I normally change 12% of water every 4 weeks (27 litres).

In my case I use Aquaforest reef salt and dose Aquaforest component 1+2+3+ daily. My tank is currently quite lightly stocked with corals. I dose Red Sea NO3

O4-X 1 ml/day. All via Apex DOS units. My tank is a Red Sea Reefer 250, 65g total, so this dose is quite low. As I have been trying to get rid of the GHA I have intentionally been keeping my nutrients low, close to 0 ppm Nitrates and Phosphates. Once under control I want to lift them a little, to around 5 ppm Nitrates and 0.25 ppm Phosphates so will reduce the NO4

O4-X.

Prior to dosing Reef Flux my Nitrates and Phosphates were 0 ppm as tested by Red Sea Pro kits. 1 week after dosing Nitrates are a little above 0 ppm and Phosphates around 0.01 ppm. I am changing my 225 micron thin mesh filter socks daily and cleaning my skimmer bi-weekly to ensure I don’t get a build up of rotting dead algae in the tank spiking nutrients during the treatment (normally clean each weekly). Skimmer was off for the first 3 days of treatment as advised, and Poly Filter was also removed during this time. Both back online now.

I plan to test Nitrates and Phosphates twice this week, and assuming they stay low plan to just proceed with my normal 12% WC next weekend. Would love to hear any thoughts and experience you all have had.

saltyfilmfolks · Feb 10, 2019

Well, the nopox is probably what’s feeding the Gha is the nutrients are low.

Make it easy. Wait 21 days with the reflux. And then follow with a couple water changes. You just want to get the dead organics out. And the accompanying nutrients. You may get some cyano.

Be carful chasing numbers.

Tastee · Feb 11, 2019

Thanks, I hadn’t seen any feedback about GHA using NoPoX as a food source. My NO4 and PO3 have been nearly zero for some time now so I may try dropping the NoPoX or eliminating altogether for a while, and keep an eye on nutrient levels by regular testing. Worth a shot.

mickybiocubeAIO25g · Oct 31, 2022

Be careful stopping NOPOx. The purpose of NOpox is to carbon feed for organic building blocks for the biological filter to reduce nitrate and phosphate. I was using nopox early in my tanks life and stopped easing the dose off over a month, then the GHA and bryopsis took over. I now went back to nopox with a strict WC regime of 10% every 6 days and filter change twice weekly. I have stopped the growth of the GHA bit bryopsis taking hold and I also have started a fluccanazole treatment. 8 days in now and haven't seen much of it dying yet. Bryopsis looks week. GHA hasn't changed. First 3 days no NOPOx or skimmer and all chem filtration removed for entire treatment period. Filter clean with fresh salt water (no WC on tank until at least 2 weeks after dose of fluccanazole). Eager to see the results in the next week. Hope my experience with stopping nopox helps. Don't stop unless GHA has been completely eliminated and then watch nutrients closely.