Water turning a yellowish tint

[jmccown]

I feel like I know the answer to my own question but want to throw it out for more ideas/suggestions. I am currently doing water changes every 2 weeks. 50 gallon changes from a 380 display and a 75g sump. When the 2 week time is near the water has a yellowish tint to it. After I change the water it is gone. Probably due to my bio-load. Do I need to step up my water changes to 100 gallons? Changing out 50g every 2 weeks is roughly 10% of total volume because the sump is not a full 75g. Stepping up to 100g changes would be about 22-23%. After I find a new home for my puffer maybe the bio-load will be reduced to a normal level. Someone take him...

BTW, all the fish are fine and healthy, never had any problems with parameters either. Nitrates are always 0. Sometimes I wonder if my test kit is inaccurate. It's one of those saltwater master test kits.

What's the consensus - 100g or stick to 50g?

 

[Travis L. Stevens]

50g water change and use lots of activated carbon. It should clear up rather quickly. Do you have Caulerpa in the system?

 

[jmccown]

I use chaeto in my sump, but I don't use carbon. I use to and it stayed really clear. But I had a purple tang get a bad case of HLLE and read somewhere that carbon sometimes causes HLLE, so I quit using it. The purple tang is 98% healed back. I later learned that I had a bad pump and replaced it, so I could have had stray voltage leaking into the tank too. The carbon probably was not the culprit there. I'll try some carbon again and see what happens, can't hurt.

 

[phljess]

If you grow a lot of macros in your sump they will cause discoloration of the water. As Travis stated, more activated carbon, maybe run it in a reactor. Also you may need to cut back on some feeding.

 

[jmccown]

I only feed 1x daily. I have my lights set to come on when I come home from work after 5 p.m. No sense in them being on in a FO setup when no one is home. So they are on about 6 hours in the evening till bedtime.

 

[WVfishguy]

I won't run any tank without carbon. The "carbon causes HLLE" fallacy came from a public aquarium looking for a reason as to why their livestock was dying. And even that anecdote came from a release of carbon dust in the water, not just from carbon in the system.

I have razor caulpera and Halimeda (!) in the refugiums of at least four tanks and never get cloudy water.

If the reagents for your test kits get old or too warm they stop working. I'd have someone else test your water to see if they get the same results you do.

Since you're skimming with a G4, the 50 g. changes should be ok. Frankly, I'm surprised you have discoloration.

 

[jmccown]

It's just the last couple days before the water change. After the change it's fine for almost 2 weeks again. I started running carbon again last night and the discoloration is nearly gone. Problem solved.