How should I lower Phosphate, and curb algae?

[NShirke]

Hi,

I'm new to reefing world, so I'd start by saying I have less to no experience. I started ~5months back. I have read through research papers and watched hundreds of youtube videos about controlling nutrients. I have a 40G breeder tank, with only a few corals, some fish and dry rocks in it. I'm using Mars Aqua Led light, which is hanging 11inch above the tank. It's 9hrs switched on everyday (day light on for 5hrs) . Red, Green and white spectrum are set to < 5%, while blue channel is set to 80%.

I'm unable to get phosphate lower in the tank. Perhaps, this is causing algae bloom too. I feed my fish twice per day as much they consume in 5-10mins or so.

Corals - Acan, Zoas, Duncan, Chalice
Fish - 2 Blue Regal tang, 2 ocellaris Clown fish
There are a dozen snails (clean up crew).

Filteration -

• Wet dry Sump
• Bio ball
• Open box skimmer(Red Devil, purchased on amazon)
• Chemipure Elite carbon
• Seachem Phosguard

Salt -

• Red sea pro

Water parameters

• Alkalinity - 10dkh
• Calcium - 420ppm
• Temp - 78k
• Salinity - 1.023sg
• Phosphate - 1ppm
• Nitrate - 0ppm

Recently, I read an article by Randy Holmes-Farley on dosing Vodka or 5% acetic acid vinegar. I remember he mentioned, if nitrates are low (which the case here), so vinegar/vodka dosing may not help to lower phosphate. However, I started vinegar dosing a week ago, and currently dosing 7.2ml each week. Should I continue dosing vinegar as my carbon dosing or any alternative? Any other methods to get phosphate lower?

Thanks

 

[SeaDweller]

I’d change your PO4 removal media to something like high cap GFO or Rowaphos. I don’t think the Phosguard works as well. I’m not sure how much you’re actually feeding but is it a lot for only 4 fish? You don’t have much (i.e corals) to consume the nutrients produced in your tank, other than the algae.

I’d remove the bio balls if you could, perhaps get a better skimmer. Water changes may help, but you’ll have to do a few, and even then PO4 can leach back into your water from your rocks, sand, etc.

You could run some macro algae in your sump if it allows. Are you using RODI to make your water?

 

[JimWelsh]

What method / tester / kit are you using to test for PO4?

 

[NShirke]

What method / tester / kit are you using to test for PO4?

@JimWelsh, I use master reef api test kit. Not sure I should go with Hanna instrument


@SeaDweller , thanks for your suggestion. Yes, I'm using RO/DI water. Re: Macro Algae, isn't my tank a bit young to run macro algae? Also, I made a few water changes in past weeks, it hardly made any dent. Just curious, why do you recommend to remove bio balls?
Finally, I feed my fish as much they consume in 5-10mins. There are no left overs.

 

[Snoopy 67]

Bio balls are nitrate factories, with corals nitrate should be under 10 ppm, with fish it is of little concern.
API is not the best for a tank with corals. Salifert or Red Sea would be better, Hannah instruments are good too. Running GFO in a reactor is the way to reduce PO4. Magnesium is necessary to help Calcium & Alkalinity in balance so you will need to test for it & keep it around 1300-1350. And yes you are over feeding + adding phosphate to the tank water.

 

[Skynyrd Fish]

Your tank has 0 no3. In this situation it will limit its ability to process po4. GFO will work, or up the no3 slightly and slowly to help the tank process po4. Bio balls are no3 factories, however you are not able to register any on your test. You could leave them, or slowly remove some weekly. Water changes will help also. I do want to add that dosing no3 can be a bit slippery if you don’t test daily while dosing.

 

[Skynyrd Fish]

I want to add have a po4 test with a Hanna. Maybe an lfs has one. I’m betting the better test will have more favorable results.

 

[NShirke]

@Skynyrd Fish and @Snoopy 67 thanks for your input! I'm going to add phosBan as my phosphate removal media. I'll keep you posted if it helps...

Forgot to add, I changed led lights from Macro Aqua led to Radion? I think algae built has decreased but I still have phosphate issue. Algae would start accumulating on tank glass next day after I clean using Macro Aqua led. It has been 3days I installed Radion Pro, no accumulation yet.

 

[Daniel@R2R]

Better lighting has definitely helped. I noticed the same difference when I switched to radions. I'd recommend reducing feeding. What the fish consume in a couple of minutes is sufficient.