PO4 tests in GHA struggle?

[Scoot]

Been fighting a bit of a GHA problem in my 180. (brief history) I've been doing bi-weekly 25% PWC's for awhile now, am barely feeding, and am not overstocked in any way, am using RO/DI, which is fed from a charcoal-filtered house-wide filter (usually 0 or 1 ppm solids reading on my digital solids tester), am using IO Reef Crystals. No fuge.

Two weeks ago I spent one entire day scrubbing every rock clean. The tank is too deep to siphon and scrub at the same time, so I run both sump return pumps to increase flow through the sump socks, and netted out any filaments. After I was done I blew detrius off the rocks, repeatedly, then swapped out sump socks (which were green as could be). Found no filaments after that. I have about a half dozen astrea's, and a few hermits (my triggers seem to have eaten most of them).

I'm starting to see tufts of GHA again, on about a dozen rocks. Nothing long, just little tufts of it, starting to carpet its way across a few areas.

I've been trying to measure PO4 with an AP test kit - not able to get good results. There are two colorimetric cards, one for FW, one for SW.

The color matches against the lowest FW reading - but isn't anything close to a color on the SW card.

Anyone else run into this prloblem with PO4 tests? There aren't any available locally, so I'd have to order a new one if this one is bad.

[melosu58]

I have heard reports that IO users have more algea problems. Even saw a test that used many of the different brands of marine salt and it said that IO was more prone to algea problems. Have you ever thought of trying a different brand of salt?

[Kurt_Nelson]

I think the algae problem I read about were with IO (Instant Ocean) and not Reef Crystals. Scoot mentions "IO Reef Crystals", but I think meant "Reef Crystals". IO and Reef Crystals are two different salts.

[melosu58]

OK yes I didnt see that . Sorry.

[Sadielynn]

I am currently going through the same thing and I have it on all but I am able to scrub 80% of my rocks down and just finished a 50% water change , I too am using IO salt . I use the phosphate kit from seachem and get fairly good results ( phosphates are reading low and nitrAtes at less than 20 I attribute this to the posphate sponge however I have a feeling that it could be just high enough to allow them to grow I need to get some chateo to help absorb this some as well) , I added to our filter a phosphate sponge and have moved power heads around to see if that helps ,. Issue here is that we are over stocked but I feed only 2xs a week , nothing seems unhappy with that schedule , I had one that I only fed monthly and he seemed fine . Only thing I can figure is that it is the new bulbs that I put in about 1 month ago ... and that I had been over feeding for a while due to inattentiveness . I guess that I will keep scrubbing away and siphioning away since there is no way to get 100% with out a tear down I will try to keep up with it by changing out a gallon a day till I nab it then one or 2 more large changes as well , I really hope to not go dark for 3 days cause that lights the room LOL ... I also get a fair ammount of light in the room with the cage lights and windows , so I may foil or paper the sides up to the top to prevent the light from getting in and just peeking now and again to see if every thing is fine ...I kinda got fustrated and backed it down to 20% when I did not get it the first 2 times however I think the water may have been contaminated ? Not sure tho but I dumped for safty any ways I mixed a fresh batch yesterday and have a new batch at the ready to mix for next weekend ... so for now we can both be miserable together while fighting this mess

[Scoot]

Instant Ocean is the manufacturer, Reef Crystals is the product. Technically, their other salt line is named "Sea Salt", not "Instant Ocean," although IO uses that name to refer to their standard salt all the time.

I have thought about trying another brand - but each of them seems to have their drawbacks with cyano, calcium, etc. RC seems to consistently be preferred.

I'm still seeing a bit of the algea returning (nothing over 1/8th inch, more of a fine carpeting on a few rocks).

Going to have to go through another scrub. Sigh. I feel like I've been starving my fish lately - the triggers have been grunting at me - I think they're mad!

[kay-bee19]

Are you soaking/rinsing frozen food in RO/DI water to reduce the amount of phosphate entering the tank and do you have any sort of phosphate-export measures in place? (phosphate reactor, etc). How often are the filter socks cleaned out?

[roka64]

I had a huge problem with IO salt mix, both hair algae and cyano. I switched to reff crystals and have had no problems since.
What are you feeding?
How long do you run your lights?
Do you have any sort of filter, if so, what kind?
Keep in mind, if you scrub the hair algae off in the tank it will help it spread.