Jimmy's Angels
Drawn from your 13 photos: a Satellite Freshwater LED Plus on its 24-hour controller, the ColorCast back glow, citric-acid CO2 and a humate base under the soil. That's about 27 fish in 5 species and 6 kinds of plants, making roughly 32 mg of ammonia a day. Counts come from photos and the tank size is a guess, so adjust both in the ammonia budget.
What's in the tank
Above the water
Fish
Plants
Substrate and hardscape
Equipment
Ammonia budget
Fish turn the protein they eat into ammonia. A standard aquaculture estimate puts it at about 5% of the food's weight for 45% protein flakes and pellets. Here it's split by species at your counts. Fix any count and the whole page follows.
The light spans nearly the whole tank and the back film suits a 48 in tank, which is usually 55 or 75 gal. The math counts 80% of it as water, about 167 L, after soil, rock and the gap under the lid.
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Cardinal tetras
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Colombian tetras
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Angelfish
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Rainbowfish
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Golden algae eater
Total: 27 fish weighing about 57 g, making 32 mg of ammonia a day.
Why the strip still reads 0. Bacteria in the filter turn ammonia into nitrite and then nitrate within hours, so it never builds up. If you ever see 0.25 ppm or more, feed less for a few days, change 30% and check the filter. Your low pH softens the blow: at pH 6.6 only about 0.2% of the ammonia is in the toxic NH3 form, against about 1.5% at 7.4.
Plants. The crypts, swords and moss take up some ammonia and nitrate directly, a little more with CO2. They're slow growers, so count on the filter for ammonia and on water changes for nitrate, and expect your nitrate reading to land below the number above.
How these numbers are worked out
- Weights come from the fish sizes in your photos and standard length-to-weight ratios: cardinal 0.35 g, Colombian 3 g, angelfish 10 g, rainbowfish 5 g, algae eater 9 g.
- Daily food is a maintenance ration for adult fish: 1.5% of body weight for cardinals, 1.25% for Colombians and rainbows, and 1% for the angels and the algae eater, fed six days a week.
- Protein is 45% for flakes and pellets and 33% for algae wafers.
- Ammonia-nitrogen = food × protein × 0.092. Protein is 16% nitrogen; fish digest about 80% of it, excrete about 80% of that, and 90% of what they excrete is ammonia. Multiplying by 1.21 converts it to total ammonia, which is what the strip reads.
- Water is 80% of the rated gallons, after soil, rock and the gap under the lid.
- Each mg of ammonia becomes about 3.6 mg of nitrate. With the same change every week, nitrate peaks at the weekly amount divided by the fraction you change.
- Treat every figure as ±50%. Feeding twice as much doubles all of them.
Feeding plan
Twice a day, six days a week, with one fast day. Give what's gone in 60–90 seconds. At these counts that's about 0.33 g per feeding, 4.0 g a week.
A day in the tank
- CO2 solenoid on
- Light and back glow fade up
- First feeding
- Second feeding
- CO2 off
- Lights off, air pump on
- Algae wafer on Tuesday, Thursday and Saturday
Shift the clock to suit you, and keep the gaps between steps.
The week
| Day | Morning | Afternoon |
|---|---|---|
| Mon | Micro pellets | Flakes |
| Tue | Flakes | Frozen brine shrimpWafer after lights-out |
| Wed | Micro pellets | Flakes |
| Thu | Flakes | Frozen mysis or bloodwormsWafer after lights-out |
| Fri | Micro pellets | Flakes |
| Sat | Flakes | Micro pelletsWafer after lights-out |
| Sun | No food. Test the water, then change 25%. | |
Who eats where
- Rainbows and Colombians grab food at the surface first. Give them their share at the right end.
- Cardinals eat mid-water with tiny mouths. Crushed flakes or micro pellets at the left end, right after.
- Angelfish take pellets mid-water and love frozen food, which is why it's on Tuesdays and Thursdays.
- The algae eater gets a wafer after lights-out, and none when there's algae on the glass for it.
Weigh a few of your usual pinches on a 0.01 g scale once and you'll know what 0.33 g looks like. Away for 3–4 days? Healthy adults are fine without food. Skip vacation feeders, which foul the water.
Things to check
Quick jobs that sharpen the numbers above or head off problems. Your checks stay in this browser.
Light specs from Current USA retailer listings; everything else from your 13 photos. Counts, fish weights and every ammonia figure are estimates. Drawing not to scale.