A few things.
First, you reported very few accurate parameter readings for either your tap or tank. I saw 82F for water temp and 0-2ppm for ammonia in the tap. But what are the tank parameters and the rest of those for the tapas well: pH, GH, KH.
I keep true altum angels. To my knowledge there are not albino altums. What you have are albino Peruvian "altum" which is not a Pterophyllum altum it is a Pterophyllum scalare.
I have also had a 3 stage RO/DI unit form a number of years. I am space constrained and I use a portable unit. I got it specifically to deal with wild altums angels. I also just replaced it with a 4 stage unit. I have excellent well water Over the 23 years I have kept fish it has had a pH between 7.0 and 7.4. But is also contains excess CO2 when it come from the tap. So, before it is out-gassed, the pH reads in the low 6s. Over the years the TDS has been as low as 55 ppm and as high as about 110 ppm. Think KH between 2° and 5° and GH between 3° and 6°. The numbers change depending on the frequency and quantity of rain and snow in any given season.
Here is where I bought my units and they are portable. I have a sink with the faucet adapted to allow a graden hose size connector to screw into it. My units come with a compatible connector. I put the output of it into a 20 Gal. Rubbermaid/ I store 20 gals. in 1 gal jugs. and another 24 gals in bigger containers. I batch the changing water in a Rubbermaid next to the tank and use the same monitor probes in the can to allow me to batch changing water at the parameters need for any given water change. I usually target a pH 6.0 and a TDS under 70 ppm for the tank and adjust the changing water to be where I need them for that.
My original 3 stage RO/DI cost me about $125 + shipping. Today is is a bit more. I just did my first run with the 4 stage unit (cost $159): sediment-->carbon-->RO-->DI. It makes pure water. I do not remineralize, I mix my changing water at 11/9 ratio RO|DI/Tap. In the winter months we also batch RO/Di for my brother to use in his humidifiers. He uses up to 3 gallons a day in the driest coldest months.
In order to monitor all of this I have a Bluelab Guardian monitor. I paid less than the current price. Mine is the most basic version and they come with wireless connectivity etc. If you want the features and will pay up for them:
Bluelab Guardian
I also have a couple of digital TDS pens. You can get these pretty cheaply on Amazon.
HM TDS-3
As for ammonia, we cannot simply assume that any level we see on a hobby test kit is necessarily dangerous. Most kits measure Total Ammonia (TA) which includes ammonia (NH3) and ammonium (NH4). The former is very toxic while the latter is much less so. How much TA is in each form depends upon the pH and temperature of the water, The higher these are, the more toxic the TA becomes.
I wrote 3 articles for another site similar to this one but way way more active. Here is the part about how to work with ammonia:
SOME IMPORTANT FACTS ABOUT AMMONIA
Ammonia in water exists in two forms.
NH3, which is the familiar nasty gas we know. Fish exhale NH3. Rotting organic matter will also create ammonia. This stuff is highly toxic and will definitely be harming fish by the time it reaches a concentration of .05 ppm (Some fish and inverts need even lower levels to be safe). However, most of the ammonia in water exists in the form of ammonium which is
NH4. This is way less harmful. But in sufficient concentrations and/or exposure times, it causes external burns. The typical test kits we use measure
Total Ammonia (TA) which is the sum of both NH3 and NH4.
Knowing how dangerous any level of TA might be requires that one know not only how much total ammonia there is but also how much of that total is in each form? The answer depends upon two other water parameters- pH and temperature. The higher the pH and/or temperature, the more of the TA that is in the toxic NH3 form. To calculate how much of the toxic NH3 form of ammonia requires that you know what the
pH and
temperature of your tank water are. Once you know all three numbers (total ammonia, pH and temperature) there is a formula for calculating how much of the total ammonia is in the form of NH3. It is way more complicated to use than most of us can handle. Fortunately, there are charts and tables available for this calculation. There is also currently a handy dandy ammonia calculator you can find here:
http://www.hamzasreef.com/Contents/Calculators/FreeAmmonia.php
1. Choose NH (NH3 + NH4)*
2. Enter in the total ammonia reading from your test, choose ppm.
3. For a fresh water tank, enter 0 for the salinity.
4. Enter your tank’s current pH.
5. Enter your tank temperature and choose F or C, whichever applies.
6. Click Calculate.
The number you want to know is the one for
NH3.
[* If your kit measures ammonia as nitrogen aka –N, choose NH-N (NH3-N + NH4-N) in step 1. above.]
Also, the EPA has no standards for ammonia in drinking water. However, what usually causes it is the use of chlormaine as opposed to chlorine as the primary disinfectant. Chloriamine is made by combining chlorine and ammonia. When we use dechlor on chloramine, it causes it to rbreak down into the two components. The dechlor neutralizes the chlorine. Depending on which brand one uses, it may also detoxify ammonia. It does this by converting it to NH4. The bacteria can still use this but do so less efficiently that they use NH3.
The amount of ammonia created by breaking down chloramine in a cycled tank is usually so low that it gets consumed by the bacteria pretty fast. The bacteria multiply when there is more ammonia available than they need to thrive.
Lastly, one of the Ph.D. folks in the hobby whom I greatly respect says one should never feed beef heart to any fish. I have kept discus in the past and DD black angels as well. I never fed beefheart. My altums have never tasted it either. So you were correct to stop feeding it. I know some discus folks will say to feed it. I do not agree.
