High phosphate

Carp890

Fish Fanatic
Joined
Jan 20, 2022
Messages
93
Reaction score
46
Location
Manchester
New to marine tanks.
Just cycling new tank 3 weeks in using all in one fish in.
PH 8.2-8.4
AMMONIA. . 25ppm
NItrite 0
NITRATE 5.0ppm
Calcium 500ppm
Carbonate 196.9ppm
Phosphate. 50-1.0ppm
Phosphate is very high (tanks in the ugly stage brown alge bad) is the high phosphate reading fueling the alge? I tested the salt water I got from store for phosphate it also showed very high?? Is this correct, I thought it should be 0 ppm not sure what to do please help me
 
If by brown algae you mean cyano, that stuff loves even a little phosphate. But it would also suck it all up usually and you wouldn't see much reading on the main tank unless it's really quite high If premixed water from a good store is showing high reading though then I am somewhat skeptical about the test kit. fish in cycling can easily cause cyano even with perfect water going in. If possible it would be good to verify that reading with a different kit or if the store will test it. Not impossible they have an issue with their water system, just not the most likely thing.

If it is giving a true reading on brand new water then you need another source of water asap. For the tank itself, if you have carbonate based rock (live rock or dry rock that you're colonizing usually is for marine) then even a 100% wc may not get rid of the phosphates since the rock will hold some and release it slowly over time. Best way to deal with the cleanup after getting better water and a large wc is granular ferrous oxide (GFO, little brown particle stuff) or the green aluminum based filter pads (GFO is usually more effective).

Right now though that ammonia reading is the more problematic thing. Fish will be much more affected by that than the phosphates. 3 weeks in I would expect the ammonia to be gone if the cycle was going properly. What is your filtration? How much rock are you using band did you get it live or dry?
 
If the store is using reverse osmosis water to make up sea water, then it should have 0 phosphate in.

If the store is using tap water to make up sea water, then it could have phosphate.
 
If by brown algae you mean cyano, that stuff loves even a little phosphate. But it would also suck it all up usually and you wouldn't see much reading on the main tank unless it's really quite high If premixed water from a good store is showing high reading though then I am somewhat skeptical about the test kit. fish in cycling can easily cause cyano even with perfect water going in. If possible it would be good to verify that reading with a different kit or if the store will test it. Not impossible they have an issue with their water system, just not the most likely thing.

If it is giving a true reading on brand new water then you need another source of water asap. For the tank itself, if you have carbonate based rock (live rock or dry rock that you're colonizing usually is for marine) then even a 100% wc may not get rid of the phosphates since the rock will hold some and release it slowly over time. Best way to deal with the cleanup after getting better water and a large wc is granular ferrous oxide (GFO, little brown particle stuff) or the green aluminum based filter pads (GFO is usually more effective).

Right now though that ammonia reading is the more problematic thing. Fish will be much more affected by that than the phosphates. 3 weeks in I would expect the ammonia to be gone if the cycle was going properly. What is your filtration? How much rock are you using band did you get it live or dry?
Thanks for the info, I had the water checked by another shop. Yes the phosphate was very high so I have done 50% change and added gfo and new water, the cyano has decreased by 80% no ammonia. The thing is do l mention it to the other shop?? Or say nothing. Using live rock
 
If the store is using reverse osmosis water to make up sea water, then it should have 0 phosphate in.

If the store is using tap water to make up sea water, then it could have phosphate.
I had the water tested elsewhere showing high phosphate, changed supplier did a 60% wc slight phosphate no ammonia looking good. Do l tell the other supplier??
 
I wouldn't bother telling the other store unless you visited it regularly. Then you might mention you are getting your saltwater from another store because it has less phosphate in compared to that store.
 
Last edited:
Thanks for the info, I had the water checked by another shop. Yes the phosphate was very high so I have done 50% change and added gfo and new water, the cyano has decreased by 80% no ammonia. The thing is do l mention it to the other shop?? Or say nothing. Using live rock
Sounds like you've got it back on track! That's really good.

If the original store was nice and tried to help you out getting started in a genuine sort of way that shows they care about their livestock, I would let them know - or let a particular person there know if one was especially nice. They may actually have something amiss with their system and just not know if they haven't seen signs of problems yet in their own tanks. On the other hand, if the shop seemed to not really care what was going on with their tanks or yours, may as well leave it and stick to the other place.
 
I use the API Master Reef Test Kit. I also include GFO in my sump, as well as carbon. I grow macros and coralline in the tank, so keeping PO in check is important.
Regarding the store that sold you the water, I would let them know. Sometimes we think everything is going well and then something causes parameter upheavals. Better to let them know, and they can decide what to do about it. Other tanks may get hurt by their water in the current state, especially if they are unaware of what they are selling.
 
I haven't used a phosphate test kit in a long time because I make my own water and my tanks have macroalgae, so I would never get a reading from them even if there was a problem - I would just get more growth. These days I mainly go by things like cyano and other algal blooms as indicators of phosphate issues and I change out the GFO in my filtration if things start to look off. However, in the past I used the API phosphate test kit and was happy with it. Some people also swear by the Salifert kits but they're more expensive; I haven't used their phosphate one specifically but had some of their others in the past.
 
When I had my reef the number one source of phosphate in my tank was frozen brine shrimp or Formula one frozen food. I switched to the kind of shrimp humans eat, keeping a piece in the freezer and shaving bits off for the fish, and my phosphate problems greatly improved
 

Most reactions

trending

Back
Top