Overdosing Phosguard?

[NaH20nerd]

Recently I’ve been trying to stop an algae bloom so I added a 100ml bag of Seachem’s Phosguard (Dec 17th) to my 10gal Nano.

Over the last 3 days...Sad to say I’ve lost my Starry Blenny, Clown Fish, and my Orchid Dotty Back. Inverts and corals seem to be unaffected. Maybe too soon to tell though.

Testing (Dec 23rd) showed KH to drop from 10.2 to 8.1. My PH also dropped from 8.2 to 7.8.
Other parameters remain constant (see below).

I’m only theorizing the Phosguard to be the cause as all parameters have been very stable until adding the Phosguard. Salinity 1.025, temp 78f, PH 8.2, Ca 430, Mg 1560, KH 10.2, NH3 0, NO2 0, NO3 0-10ppm, PO4 0 - .15.
I’m doing 20%-30% weekly water changes using RODI water.

I’ve since removed the Phosguard completely and replaced with a Polyfilter and GAC.

Am I on the right track here or does anyone see something I may be missing?!


Signed,

Regretful and saddened fish killer.

 

[reef lover]

Did u rinse it out first?

 

[NaH20nerd]

Did u rinse it out first?

Yes. Rinsed with tank water (outside the tank of course).

 

[mannyhernz]

why did you add that much?

 

[shred5]

I do not see why phosguard would kill fish, never heard of it doing that. Corals i could see that happening by reducing phosphates to quickly or releasing of aluminum.

 

[chipmunkofdoom2]

So you had a blenny, clownfish and pseudochromis in a 10 gallon tank? Call me old-fashioned, but that sounds like an awful lot of fish for a 10g. How many other fish are in the tank?

 

[NaH20nerd]

why did you add that much?

I bought the smallest bag avail. And didn’t know (still don’t know for sure) that PhosGuard would lower KH.

 

[NaH20nerd]

I do not see why phosguard would kill fish, never heard of it doing that. Corals i could see that happening by reducing phosphates to quickly or releasing of aluminum.

I don’t think PhosGuard directly killed the fish. But I am wondering if the lower KH and PH is what did it. No signs of disease visible...with exception to the clown fish (last to go)...he had started developing white cloudy fuzzy stuff on and around his dorsal fin. Guessing the lower PH stressed him into sickness and death. The other fish just died literally overnight.

 

[NaH20nerd]

So you had a blenny, clownfish and pseudochromis in a 10 gallon tank? Call me old-fashioned, but that sounds like an awful lot of fish for a 10g. How many other fish are in the tank?

1 Clown, 1 Blenny, and 1 Orchid Dottyback. No other fish...well, except two snails and one Fire Shrimp. All of which are still doing quite fine. Corals are all fully extended and colored up.

Plenty of room for that stock list in my opinion. Wasn’t planning on adding any more. Funny thing, tank still looked empty as all but the clown fish stayed in their little hidy holes. Clown was hosting a RBTA.

 

[NaH20nerd]

Here’s a pic of the tank so you can see the corals and such.

 

[DRTYshredCo]

Looking into lowering phosphates I found this product... the information says "100 milliliters treats 60 US gallons". Having a 10G myself I am contemplating using a tiny amount (1/6-1/4 of bag) to see if it makes a difference. I assume using the whole 100 ml would be over-kill. *I will note that I am new to the game so my comment is purely an assumption.

 

[moz-art]

How did it go with phosguard?

 

[moz-art]

Hi I am just curious how is your tank doing and are you satisfied with phosguard after all? Do yo my recommend to use it?

 

[NaH20nerd]

It seems to be doing its job in the correct dosage. I change it about every two weeks.