Reef Algae help please!

[cgthebeast]

How do you keep your reef tanks algae free for the most part?

I feed lightly, maybe three times a week
I have a 7 hour light period
My tank is mature
My phosphate test kit show 0
My parms are stable at
Salinity 8.3
Ca 465
Mg1330
Kh 9
Temp 78

I skim my skimmer at the wettest possible and it's over sized for my 75g

I have a sump that grows excess algae, though I really should work in it

I haveing some issues with cyni and dinofllagyes but I don't know why, it's not over taking my tank but I have to scrape algae everyday and my sand bed looks splotchy and just bad and purple. I know it isn't flow cause even in places with high flow it's hanging on

 

[Sniperhank]

The lights in your display are out producing the sump when it comes to removing nutrients.
It takes many water changes with ro/du water to solve these issues. Even in my Reef tank I have Cyanobacteria that creeps up. By siphoning it out during water changes my ats has taken over and absorbs the nutrients out of sight and out of mind.

 

[cgthebeast]

Yeah I also use ro/di water, though my system is old and I'm suspecting that might be the source of my problems, I plan to get a new one from BRS as my original was just a cheap thing I got of eBay,

I also do a 12% water change weekly with instant ocean reef crystals,

 

[Sniperhank]

An old system shouldn't be an issue if you have been replacing the filters, depending on water source can range from 4-6 months, and resin when it is depleted, which also varies on water source.

 

[cgthebeast]

Right, it's just a old system like 8 years and younger me did not take care of it properly. So instead of rebuilding and buy brand cartagiages I'm just gonna go head and replace it cause I know it's a issue cause every time I top off my tank my skimmer goes crazy

 

[Sniperhank]

Have you checked the tds coming out of the system?
I just got myself Aquatic Life's twist ro/di unit and am really loving that I replaced my older BRS model with it. Saved me a ton of space.