Low nutrients? Halimeda in my SPS tank

[swhaley40]

To start off,I haven't had a positive test for nitrates and phosphates for months(though I'm starting to think they're there). I used to just dose vodka, now I'm dosing Brightwell Biofuel, Bak 7, and amino acids. My SPS colors are good, but they are lighter than most of what I see on RC. For example, my ORA green slimer looks more yellow than green, red milli looks more pink... I've also thought this might be a "not enough nutrients" issue. My question is in regards to macro algae....Halimeda loves my tank. I have tons of it and a new "bush" sprouts out of the live rock or sandbed every couple days. If my tank was extremely low nutrient, would the Halimeda survive? Could the halimeda be masking the nutrients? About a month ago I increased feedings to see if I could improve color...haven't seen any changes., but have recently had an aptasia explosion. I've heard that can happen when you feed too much. I'm confident this is not a photoperiod issue. I run 3 bulbs(2 blue plus, 1 fiji) for 10 hours per day, all seven bulbs(2 blue plus, fiji, 2 aquablues, 2 AS 22K) run for 4.5. Anybody have any ideas? Anyone run a low nutrient system with Halimeda growing well?

[Tater11]

if im not mistaken halimeda uses calcium for growth.not po4 no3.

[swhaley40]

Yeah, it uses a ton of calcium..just wasn't sure if it requires some nutrients to grow.

[Marklu]

It definitely needs nutrients.

[BlAcK_PeRcUlA]

Halimeda can grow well in high ca, low nitrate, low phosphate environments. I would just keep pruning it with your other maintenance. A little bit is attractive in my opinion.