Wed, 05/25/2005 - 17:17

Phosphate.

My PO4 levels have been elevating for a couple of months. If you refer to this page, you'll see they were going down, but rose up again for a few simple reasons. http://www.melevsreef.com/parms.html

Oceanic salt issues, lack of water changes, running out of PO4 media remover, skimmer not built for the system's bioload....

As you may know, I use the Phosban Reactor. I've been using one for about 7 months, maybe longer. Here's what it looks like, hanging on the edge of my refugium. Btw, if you look closely, you'll see how the water weeps out of the teeth quietly into the return section. That is something many people ask about, because they worry about the water falling and creating microbubbles. It isn't a problem if the flow is within an acceptable range.

Tunze has released a new product that removes Phosphate and Silicate.

Here is the device they suggest, filled up with the media and mounted beneath a Tunze 400gph powerhead. This powerhead is attached to the glass with a Tunze Magnet. I would say it held about 1/3 of the product from one container, maybe a bit more.

I tested the PO4 level yesterday, and it was darn close to 3.0, but I'll call it 2.5 just for kicks. I use the Saliftert PO4 test kit.

Since running the Tunze media for 24 hours, PO4 is about 1.5 now. I called my supplier today to ask if I should change out the media now for the next 24 hours, but he suggested I let it run until I don't see a change with the test kit. Makes sense.

I believe that little holding container runs $30 (to hold the media), if you have a different powerhead that you'd like to use to do the same task. This one looks very similar to my older Tunze Turbelle, with much less flow. My Turbelle moved 800gph, if I recall correctly.

I'm going to test my water again tomorrow to see what the reading is. I'm sure it will be a little less, as I added about 70g of new saltwater when I installed this sump, and dumped a lot of nasty saltwater and detritus when I removed the older sump. Much of the macro algae had detritus accumulated within itself, and this was shaken out before it was placed in the new refugium.

The label on the Silphos states:

Tunze Silphos is an adsorbing granualte on an iron basis for fresh or salt water, which removes silicates and phosphates from the aquarium water. Silphos is highly effective, safe and binds with silcate and phosphate to the granulate, decreasing undesirable growth of algae and preventing the developoment of mucous algae. Silphos has a very high bonding capacity and should be used very judicously.

Suitable for two TUNZE refill units 870 or one 1670. The contents corresponds to about 1000g (35.2oz) Bonding capacity of 1000g (35.2 oz) of TUNZE silphos: 280g (8.8 oz.) of phosphorus and 80g (2.8 oz.) of silicate; grain: 4 to 6 mm (.15 to .23 inch).

Prior to use, check the concentration of phosphate! It is not advisable to use Silphos at excessively low phosphate concentrations (below .015 mg/l)!

Use and Dosage
Use a maximum of 200g (7.05 oz) for 1,000 liters (264 gallons) of water at the beginning. After two weeks you may increase the quantity up to 400g (15.1oz) for 500 liters (132 gallons) of water. Do not rinse out the material for fast removal of nutrients. Rinse out the granulate prior to use for slow removal. The material has to be well perfused.

If the phosphate and silicate concentration increases again, replace the Tunze Silphos.

Silphos reacts very slowly and continuously, thus can be retained in the water circulation. It is ideal for permanent silcate and phosphate bonding. Check the phosphate and silicate concentration in regular intervals. A lack of nutrients may cause the corals to die! Avoid an overdosage!

We rinsed the stuff out pretty well before hooking it up in the tank. I'd imagine it would work fine in a canister filter or even the phosban reactor with better flow, assuming you could put enough media in the reactor. The powerhead I'm using now moves 400gph I was told. Btw, the media basket drops off the pump when the power is off, so be sure nothing important is beneath it!

You might ask Roger in the Tunze forum on ReefCentral.com what he would suggest.