Phosphates

[Anonymous]

Alright, a little perplexed now. I have had my reef up and running in the same tank for around 5 years now. No fish in it for 3 weeks now as they were getting too big. It is a 27 hex with a bak pak and 200 gph powerhead for circulation. Water changes with RO (not DI)water 5 gallons every 2 weeks. Fed a half a dime size chunk of Rod's food to the Duncans, Acans, Brain and Zoos every other day, and 80 watts of PCs for light @ 9hrs/day Never had a problem with cyano until now. I live in an area where there is a lot of water being used for fracturing rocks for the Marcellus Shale gas, and is dumped back into our drinking water system....do any of you guys think that that may be the culprit for the bloom in cyano? If that's the case, should the RO unit take out the phosphates? Or will should I tack on the DI? I did some big 60% water changes a couple of weeks ago to try to remove phosphates (I don't like adding to may chemicals to my tank...i.e. phosphate sponges). Any help would be a boon to the old reef...thanks!

 

[Len]

Alright, a little perplexed now. I have had my reef up and running in the same tank for around 5 years now. No fish in it for 3 weeks now as they were getting too big. It is a 27 hex with a bak pak and 200 gph powerhead for circulation. Water changes with RO (not DI)water 5 gallons every 2 weeks. Fed a half a dime size chunk of Rod's food to the Duncans, Acans, Brain and Zoos every other day, and 80 watts of PCs for light @ 9hrs/day Never had a problem with cyano until now. I live in an area where there is a lot of water being used for fracturing rocks for the Marcellus Shale gas, and is dumped back into our drinking water system....do any of you guys think that that may be the culprit for the bloom in cyano? If that's the case, should the RO unit take out the phosphates? Or will should I tack on the DI? I did some big 60% water changes a couple of weeks ago to try to remove phosphates (I don't like adding to may chemicals to my tank...i.e. phosphate sponges). Any help would be a boon to the old reef...thanks!

Your RO will take out about 98% of phosphates, but that last 2% that gets by could contribute to cyano and algae. When my DI resin is getting old (TDS > 2ppm), I do see more algae growth. Therefore, I would recommend you add a DI stage. It'll take your RO's TDS down from 10-20ppm to 0.

I've also heard other people who use Rod's Food and experience cyano. I don't know if there is a direct correlation, but being that this is about the fifth time I've heard it, it is possible.

Phosphate sponges (GFO) is very safe. It's used 24/7 and needs to be changed every 6 month or so. It's a cheap nutrient export mechanism that I'd also consider (GFO + reactor should be <$100).

 

[Anonymous]

Thanks Len, I'll give the phosphate sponge a whirl.