Water Changes On A Macroalgae Tank?

[jabeuy]

I'm looking to start a small tank with only macros and fish, no corals.

 

I was wondering if people with tanks like these still do water changes. Let's say you have enough macros to keep nitrates and phosphates low, are there other elements macros need that a water change can replenish?

[FlowLikeWater]

alk, cal, and mag still play a role in macro growth and im sure a water change will help replenish micro-nutrients like iron and iodine

[gulfsurfer101]

Yes they do require all of the above minor trace elements. Not much but a couple gallons every other week and you'll be ok I imagine. First of all what size tank are w talking here though. Remember that trace elements are consumed much faster in a smaller aquarium.

[jabeuy]

Damn! Changing a few gallons is no issue at all, just thought I'd be able to get away with none lol

 

This would either be a 7g or one of those 10g fusion nuvos.

[ReefWeeds]

what they said I actually find that I need to continually feed the tank to have enough nutrients present for the macros otherwise they start to kind of wane. And macros definitely use magnesium - and the calcareous ones like halimeda will suck up some calcium for sure.

[gulfsurfer101]

A 2g wc in a 7g macro goes a long ways imo! You'll be fine with doing one every two weeks. Can't screw it up.

[jabeuy]

what they said I actually find that I need to continually feed the tank to have enough nutrients present for the macros otherwise they start to kind of wane. And macros definitely use magnesium - and the calcareous ones like halimeda will suck up some calcium for sure.

Ooh, do you have a build thread for yours?

A 2g wc in a 7g macro goes a long ways imo! You'll be fine with doing one every two weeks. Can't screw it up.

Yeah definitely! The macros add that extra margin for error

[ReeferReefer]

Well you will be able to get away with more if you are dosing two part. I would start with bi weekly small WC and back off to once a month and keep a close eye on it. You can decide how often you need to change the water after that and the tank settles and is having good growth.

[vlangel]

Ooh, do you have a build thread for yours?

 

Yeah definitely! The macros add that extra margin for error

I just started a little pico macro/softie tank. It has a clownfish and some brackish converted to salt gobies in it as well. Its Baby'aBode in the pico section if you are interested.

[Subsea]

I'm looking to start a small tank with only macros and fish, no corals.

I was wondering if people with tanks like these still do water changes. Let's say you have enough macros to keep nitrates and phosphates low, are there other elements macros need that a water change can replenish?

Consider that macros add complex DOC compounds to the water as do corals and fish. While macro will assimilate inorganic fertilizers like nitrogen and phosphate, it will not reduce DOC. Activated carbon removes 50%-70% DOC, Efficient protein skimming removes 20%- 30% of DOC.

 

I like small water changes once a month in conjunction with activated carbon used 24/7 and replaced bimonthly.

[yoshii]

+1 to what everyone else has been saying. In my 10g I got away with like 1-2 water changes a year, but I dumped food in like crazy and dosed alk and ca. Also, certain macros need more iodine, iron, mag etc. than others.

Subsea, hm I didn't even think about that. I ran carbon in my macro tank too