Re: Elevated Phosphates
To: INET::"Aquatic-Plants at ActWin_com"@RNISD0.ENET.my.domain
Subject: Re: Elevated Phosphates
Date: Tue, 12 Mar 1996 12:31:16 -0500
From: NAME: DIONIGI MALADORNO
TEL: 201-812-3495 <MALADORD@A1@RNISD0>
To: "Aquatic-Plants at ActWin_com"@INET@RNISD0@MRGATE@RNISD0
Thanks to the nice guys who had pity of me and volunteered to help!!
I have a 180 gal with a good amount of plants (20-30 echinodorus, 15 crinum
, cabomba, Java fern and few others submersed plants I am trying out.
Additionally I have mixed floating plants: duckweed, frogbite and pistia),
medium fish load (is it really medium, at least for fishkeeping standards?:
6 green discus, 14-16 Pristella tetra, 4-5 Neons, 2 L. curviceps, 6
Rineloricaria sp. and 2-3 Peckoltia). The substrate is gravel, with a lower
layer containing some laterite, peat and Delaware Imports tablets.
Nitrates are <9 mg/l, pH around 6.6, CO2 injection for 2-3 hours/day (my CO2
levels are consistently high), 84 deg. Farenheit, GH of 4-5 and KH of 3-4,
iron 0.4 mg/l, which I am planning to lower to 0.1-0.2 mg/l. I set up the
tank last July. I have three stacked sponge filters driven by a power head
(won at the monthly lottery of the North Jersey Aquarium Society, nice
people there), a Fluval 404 and a Superking. I don't mind water changes (my
tap water is soft and quite good), and I change 10% of it at least 3
I got very enthusiastic about peat filtration, and I have used an average of
two 10"X4" mesh bags filled with peat in the Fluval basket. I used
pelletized peat bought in an aquarium store, but also boiled gardening peat.
I have four 3' fluorescent lights driven by an Ice Cap VHO ballast: they are
on 12 hours a day.
The fish seemed consistently happy, but dark slime "algae" (cyanobacteria,
right?) kept growing everywhere, although at a low pace. In addition, all
plants develop after a while a greysh or dark "mineral"-looking layer on
their leaves: I had a few diatoms growing in other tanks, but they looked
more like dark spots, while these are more uniformly spread. Most plants
grow, but in a stunted manner.
I tried to modulate lighting levels using the floating plants, but with no
real changes. I also keep cutting the older and damaged leaves, but in most
cases the new ones are fewer than those I cut. Only the cabomba and the
crinum do consistently well.
So, here we are (finally!!) to the phosphate levels. After I ordered from
HACH a better kit that the Red Sea I originally had, I realized they were 4
mg/l. My tap water has 0.4 mg liter, I feed the fish quite sparingly and
change the water often (nitrates would not be good otherways), so I began to
suspect that the source of all my trouble was the peat.
Here is what I am doing: please let me know if there are better suggestions:
1) I have eliminated all peat from the filters and cleaned them all. I hope
that this will also reduce the silt deposited on the plants, which I guess
was leaching out from the gardening grade peat. The CO2 injected seems
adequate to control pH by itself.
2) I bought several pouches of Phos-Zorb, which I am using one at a time,
replacing it when phosphate levels stop dropping. I started using them a
week ago. I am now at the second one, and the levels are now around 1.5
mg/l. No sign yet of clear improvement in plant growth.
3) What levels should I realistically try to achieve? Because of the tap
water phosphate content, I guess that only the use of resin or membrane
filtration of the tap water could bring the levels below 0.4 mg/l. Are these
levels compatible with adequate algae control? Would the plants be enough to
pick up measurable amounts of phosphates and successfully compete with the
algae and cyanobacteria?
4) Phos Zorb pouches seem quite effective and do not cost too much from mail
order catalogs. I used in the past other anti-phosphate resins in other
tanks with less success. If I will have to bring and keep phosphates down to
0.1 mg/l or so, maybe I should just use Phos-Zorb consistently, at a lower
cost and inconvenince of a water filtration system. Has anyone any idea if
this may really be a cost-effective solution?
5) Does anyone know if the more expensive Fluval peat is low in phosphates?
I would not expect so, and probably I will not use peat anymore. Unless it's
just that I used too much: what's the dose per gallon?
Thanks a lot in advance to those that will reply.
So, I'm quite happy with , which I
consider quite reliable since I use HACH kits (I think they are worth the
money because they make you save a lot