How much water to change

[cgthebeast]

I have a very lightly stocked 75g reef tank with only two juvi clown fish and a 1.5in six line wrasse. I feed every other day, alternating between flakes and frozen fairy shrimp. I run a sump packed with algae, charcoal, and filter media. How much water do I change

[Reefing Madness]

Depends, whats your Nitrates telling you? With macro algae in the sump, is your water fine? Run a skimmer also? What size?

[Marty.h]

What's your nitrates ?

[cgthebeast]

Nitrates are undetectable I run a reef octopus 110 in sumo skimmer. Water is perfect, I use ro water and reef crystals, the tank is a newer one but is fully cycled. I test everything with an api liquid test kit weekly unless I notice something wrong. Even my skimmer dosent pull anything nasty out of the water, just a milky substance not black or anything even though it's broken in

[Sniperhank]

With that few fish I'd be less concerned about the nitrates and more interested in the corals in terms of how they are depleting your elements. I always think a 10% water change weekly is best towards this, even if you dose alk/calc as for we can't test well for many essential elements that are replaced via water changes, iodine as example.


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[Marty.h]

Depending if you have any corals that may need trace elements replenishing if not then I cannot see any reason to change any water if nitrates are 0 and PH ect good.

My system for example is a full reef with SPS but I dose elements and trace elements ect to keep everything in check and I've not changed any water in 17 weeks and my nitrates sit at 5ppm

It depends on the needs of your system and nutrient levils.

[cgthebeast]

Okay, good point. I have a small toadstool, the head is about the size of a silver dollar, a acan that has now only just cover its frag plug but is growing like crazy, a 4 headed blasto, a two headed hammer with each head roughly silver dollar size, a small frag of Zoas, and a football size drag of GSP. I plan to order one of those frag packs off reefs to go here soon, a early Christmas present, and I only deal with LPS and softies at the moment as my brother will become the care taker of the tank here in about 3 years

[Marty.h]

Then check your

Mag
Alk
Calcium

As you will need to maintain them for the LPS

[melosu58]

For the sake of your corals I would do a PWC every 2-3 weeks. With a light load you could probably get away with 10-20 %. PWC`s not only dilute excessive nutrients but replenish trace elements that are necessary for coral and fish processes.

[Reefing Madness]

Marinedepot.com | Reef Tank Parameters

[ReeseD]

I always do fifteen percent of water for regular water changes.


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