The harm of phosphates in a reef tank.

[Diverdude]

Does anyone know specifically what harm does phosphates do to a tank, besides cause an algae bloom? My level is very high, and I can not seem to keep it down. Everything else is within acceptable limits or "0".

[reefrunner69]

Diverdude......


To answer your question, high phosphates can hinder/prevent calcification in stony corals. I have read from other hobbiests that high phosphates can have an effect on molluscs like snails, although I do not know if that is accurate or not. I think before you have a problem with calcification, you are going to experience that algae bloom you mentioned, probably in the form of hair algae. You say you've tried to keep it down, how?

Methods of phosphate control

• use RO/DI water for water changes and top off
• do not feed foods high in phosphate
• use Kalkwasser regularly for CA supplamentation (it precipitates phosphate)
• use phosphate removing resins for emergencys

It is importont to control the import of phosphate to the tank, not just try to export it once it is there.

[Diverdude]

I use RO/DI water for water changes and top off, I have my own unit.

I feed my fish OSI flake food, which i don't think has a high phospahte level if any.

I have never used Kalkwasser as i did not know anything about it.

I have used Phosphate & Silicate Magnet, distributed by the Mark Weiss Companies INC. It seemed to bring it downa bit. i added it on May 4th.

I have no stoney corals. only fish, polyps,and shrimps. I am trying to grow some macroalgae(Grape Calerpa)

[reefrunner69]

Originally Posted by Diverdude

I use RO/DI water for water changes and top off, I have my own unit.

Did you fill this tank up the first time with tap water? If so, when?
How often are you doing water changes? How large?
Aaron said you tested the phosphate of the RO/DI water after it sat for a week, what about right after it was produced? Have you tested the freshly made S/W? What test kit are you using to test? Will it test S/W and F/W?

I feed my fish OSI flake food, which i don't think has a high phospahte level if any.

Many flake foods are very high in phosphates, I am not sure about OSI.

I have never used Kalkwasser as i did not know anything about it.

Kalk is a saturated solution of Calcium hydroxide or Calcium oxide, it is a balanced solution (provides CA ions as well as carbonate ions in the proper proportions for calcification), it has a side benefit of precipitating phosphates. It is my preferred method of CA supplementation. It is not that hard to do and you can replace all evaporation with it. If your interested post back and we can give you all the details.

I have used Phosphate & Silicate Magnet, distributed by the Mark Weiss Companies INC. It seemed to bring it downa bit. i added it on May 4th.

I prefer Seachems Phosgard for lowering phosphates, I have never used this product, but since I do not care for Marc Weiss or his products, my opinions would be rather biased. You said it brought it down a bit, did it go back up? or has it remained at the lower level. If it has not risen anymore then simply replace the resin, and keep replacing it as soon as the phosphate stops dropping.

I have no stoney corals. only fish, polyps,and shrimps. I am trying to grow some macroalgae(Grape Calerpa)

The caulerpa may not reduce the phosphates that much. Most aquatic plants prefer ammonium or ammonia as a nutrient. Although if these are in short supply they may take a bite out of the phosphates.

[fishfreek]

Sorry I removed my post the instant I saw diverdude had responded. Did not know that kevin had had time to look at it.

Shoot me :P

[Diverdude]

tell me more about the Kalkwasser. It sounds like a good thing.

as for the water, i started doing water changes with the RO/DI. after i bought the unit. I did a 50 gallon change then(may4th) and another 40 gallons about 2 weeks ago.

[reefrunner69]

Originally Posted by Diverdude

tell me more about the Kalkwasser. It sounds like a good thing.

as for the water, i started doing water changes with the RO/DI. after i bought the unit. I did a 50 gallon change then(may4th) and another 40 gallons about 2 weeks ago.

I'll get to the Kalk in a minute. Had to take some pics for Aaron (deleted the ones I had told him about), after I send them off to him, I'll post about the Kalk. In the meantime, how about some dates.

When was the tank set up?
How big is the tank?
Were you using tap water before the unit was purchased or another type of filtered water?
Is it municipal water?

I'll post about the Kalk in a few minutes, gotta resize Aaron's pics.

[fishfreek]

how big is this tank?

So you have changed out 90 gal so far. How long had you been using tap water? what does your water test directly from the sink? do you naturally have high phosphates?

[Diverdude]

The tank has been set up for years. I had kinda lost interest in it due to funds(went thru a divorce) and kinda let it go. it has been a fish only tank up until now.

the tank is 90 gallons.

I was using (city) tap water run thru a tap water purifier for years before the RO/DI unit was purchased

[reefrunner69]

With continued waterchanges (increase the number, do about 25% per week for a moth or so) and use of the phosphate removing resin, the phosphate will begin to come down. Even though you have replaced 90g of water, the first change did about 55% that left 45% of the phosphate in the tank. The next change was about 45%, leaving 55% of the 45% phosphate etc...

Kalk:

Originally Posted by Bang Guy posted at another site

Start with mixing a tsp of powder per gallon of water. If you have a high demand tank and you find this won't maintain your CA and ALK levels increase to 1.5 or 2 tsp/gallon.

Mix throughly and let it settle. Drip in the clear liquid making sure none of the sediment enters the display tank. There may be a film of Calcium carbonate on the surface, don't add this to the tank either.

It should be dripped slowly into the tank or the PH can rise. Try to only drip enough to replace the evaporated water from the tank (topoff). If you dose it while lights are out it can help you maintain the PH overnight.

Please ask about anything you are unsure of.

Guy

Originally Posted by reefrunner69 posted at another site

There are many different ways to dose kalk., for years I used a simple IV style doser. A good place to find some cheap dosing pumps is a DIY site/page. OZ Reef has alot of good DIY plans, look under trace element dosers.

Precautions:

• don't mix more than about 5 days worth at a time
• be careful it is very caustic
• does a good job of maintaining levels; not so good at increasing levels
• dose at night, or continuously (with a level switch)
• do not dose too quickly

Hope that helps, feel free to ask anything about Kalk, your not sure about.