Help with water params and developing algae issue

Djasak · Apr 30, 2020

What's up guys, I've just finished doing my series of tests and I have a couple values that are high. I would normally just do a water change, but I just started seeing a couple different algae outbreaks that have me a little concerned. They're small isolated patches and I dont want to start stirring things up in the tank and make it worse...so what would you guys do in this situation? The outbreaks I'm seeing are cyano, diatoms, and dino. These are all presumed based on my eye and experiences from past algae outbreaks in previous tanks. I do not have a scope to confirm what I believe these algaes are. Params are as follows:
Salinity: 1.025
Nitrite: undetectable
Nitrate: 3mg/L
Phosphate: 2 mg/L
Mag: 1560ppm
Alk: 16.1 dKH
Cal: 460ppm

Mag, alk and cal were tested using the red sea test kits.

Phos, nitrite, nitrate were tested using seachem test kits.

Thanks in advance for any help.

muzikalmatt · Apr 30, 2020

At first glance your phosphate levels and alkalinity are really high! Magnesium seems a bit high as well, but that's less concerning. With phosphate levels that high, I would not suspect dinos as they typically show up when your nutrients bottom out to zero. However, it is still possible. You might want to double-check your tests to make sure either they aren't expired or that you're conducting them correctly. Those readings just seem really off imo.

Are you using RODI water and what salt mix are you using? Assuming your tests are correct, I'd recommend testing your RODI water source to see if you're getting phosphates from there and also testing your fresh salt mix's alkalinity to see if that's why your alk is so high. Typically phosphates should be between 0.03 and 0.10 ppm. You're at twenty times that right now. Alkalinity should usually be between 7 and 11 dKH, so 16 is very concerning.

After testing your RODI water and salt mix, assuming the parameters are in line for both (zero phosphates and between 7-11 dKH alk) I'd recommend doing a series of water changes to try and get both of those levels down to more reasonable levels.

Hope this helps!

Djasak · Apr 30, 2020

Are you using RODI water and what salt mix are you using? Assuming your tests are correct, I'd recommend testing your RODI water source to see if you're getting phosphates from there and also testing your fresh salt mix's alkalinity to see if that's why your alk is so high. Typically phosphates should be between 0.03 and 0.10 ppm. You're at twenty times that right now. Alkalinity should usually be between 7 and 11 dKH, so 16 is very concerning.
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Yes I am using RODI. I just replaced all the filters including the membrane so I have doubts that's part of the source of the problem but it doesnt hurt to check. My salt mix is the hw marinemix. Red sea tests expire in july, I just realized the seachem test kits are expired. ‍

I must admit that test kits are definitely an area for me that's due for updates and upgrades.

Also found out that one of my primes had the red and green spectrums turned way up from what I normally keep them at. Not sure what happened there but i did recently upgrade them to the new generation.

muzikalmatt · Apr 30, 2020

Djasak said:
Are you using RODI water and what salt mix are you using? Assuming your tests are correct, I'd recommend testing your RODI water source to see if you're getting phosphates from there and also testing your fresh salt mix's alkalinity to see if that's why your alk is so high. Typically phosphates should be between 0.03 and 0.10 ppm. You're at twenty times that right now. Alkalinity should usually be between 7 and 11 dKH, so 16 is very concerning.

Yes I am using RODI. I just replaced all the filters including the membrane so I have doubts that's part of the source of the problem but it doesnt hurt to check. My salt mix is the hw marinemix. Red sea tests expire in july, I just realized the seachem test kits are expired. ‍♂ I must admit that test kits are definitely an area for me that's due for updates and upgrades.

Also found out that one of my primes had the red and green spectrums turned way up from what I normally keep them at. Not sure what happened there but i did recently upgrade them to the new generation.
[/QUOTE]

The expired test kit could account for the high phosphate reading, especially if you recently replaced your RODI filters. If you're looking to upgrade test kits, I highly recommend the Hanna ULR phosphate checker and the Hanna alkalinity checker. HW Marinemix is supposed to mix at around 9.0 dKH so I'm not sure why your alkalinity levels would be reading that high unless you are dosing. That could be a false reading as well.

The higher red and green spectrums could absolutely account for the increase in algae, so getting that back to normal should help. I would double-check your testing before making any drastic changes, especially if the algae patches are rather small as you indicated.