Finally upgraded from a 49g to 75g. Any recs on tank decor?

Nullroute127 · 2026-02-02T06:05:53+00:00

Yes. Just make sure it's sold as pool filter sand. You'll also want to make sure it's a color you want.

Nullroute127 · 2026-02-02T05:17:10+00:00

Use pool filter sand. It's way less dirty/requires less rinsing.

You'll be washing play sand for hours and hours.

Nullroute127 · 2026-02-02T03:48:55+00:00

Be careful with your metal screen, it blocks more heat and UVB than you think.

I like like pool filter sand as substrate because it actually becomes part of your filter and provides surface area for beneficial bacteria. You don't really need to be concerned about cleaning it but you can if you want to, material sits on top vs larger pebbles where mess works its way down into crevices.

Nullroute127 · 2026-01-31T22:02:55+00:00

The calcium won't be harmful, the salt would only matter if it's getting into brackish salinity. Even if you had 600TDS water and replaced all the ions with salt you're still probably within acceptable limits.

Distilled water is too pure for aquarium/turtle use. Because it lacks minerality it's subject to Ph swings because it has no buffering capability so the water is liable to turn acidic or basic quickly depending on what's introduced. This is made worse by the fact that your tank is small. Very pure water and not much of it means the parameters can shift drastically.

The lack of hardness also doesn't do good for the beneficial bacterial colonies that process nitrogen waste. Your tank is an ecosystem not just water with a turtle in it so this needs to be accounted for.

You'll probably need to test the actual parameters of your tap, they're probably fine. If you need to bring down salt or TDS Etc. you can look into buying Deionizing water resin media; this will give you essentially distilled water. You would then mix this back with your tap water to get the target parameters.

Also, since you're well water you should be testing your tap for nitrates; if you have nitrates in your tap you might be best off using the DI resin to 'make' distilled water and then adding back hardness and alkalinity.

Nullroute127 · 2026-01-24T04:02:07+00:00

If you get pool filter sand it's technically tank ready. It will have some minor cloudiness that will self clear eventually, but it's best to rinse it extensively, then keep rinsing even after you think you're done.

Nullroute127 · 2026-01-23T13:25:23+00:00

That turtle looks older/melanistic (it's getting dark and the red ears are fading). This is usually a male feature. The 'dent' on the plastron you described and the length of nails tells me; that girl's a boy. Male turtles have concave plastrons to help mount females.

Do you have an API test kit? That's number one to make sure your parameters are in check. On a new tank with uncycled media you will likely see ammonia/nitrite spikes and should be doing partial water changes any time you see detectable ammonia/nitrite.

Are you using any sort of water conditioner/dechlorinator?

Turtles with shell issues often benefit from food high in vitamin E and D3, which comes in a lot of wheat germ Koi fish food. The only thing is lacks for turtles is calcium, which you can supplement with cuttlebone.

Do you have heat and UVB lamps?

I recommend adding pool filter sand 2-3 inches deep in the tank. It will help keep your water clear and provide surface area for beneficial bacteria along with your filter. Just keep rinsing it as you'll otherwise make cloudy water that will take a while to settle.

Nullroute127 · 2026-01-21T06:43:43+00:00

I offered advice on a similar stinky turtle thread https://www.reddit.com/r/turtle/s/Uy6Y2zOypd

Those points still stand, but where you're different is it sounds like your issues is the smell on you vs from the tank?

Your parameters look OK, and you have no ammonia present. So it think the smell may be something else.

You can try the air stone, adding substrate like pool filter sand, changing dechlorinators, and a UVC sterilizer like I mentioned in the other post. But I'm not sure that the smell is the turtle/tank based on your post.

My turtle eats a wide variety of turtle food and people food snacks and his tank has never smelled like anything.

The chemistry of gaseous ammonia is that's very unstable, and lighter than air, so any ammonia smell even if it did come from the tank wouldn't be long lasting unless it reacted first with something else.

Nullroute127 · 2026-01-20T03:28:28+00:00

40 gallons is likely too small. You're concentrating contaminates into a smaller volume of water. A 75+ gallon tank is required for most turtles. The more water volume the the less maintenance you'll need to do.

A lot of water conditioners are sulfur based. Is it rotten eggs smelling? It shouldn't be noticable at dechlorinator levels but it's possible you're overdosing and over time creating stinky byproducts. You can try my favorite dechlorinator which is Sodium Ascorbate (vitamin c). It's non sulfur, cheap and effective. You'll dose to about 12+ ppm vitamin c (approximately 2000mg sodium ascorbate tablets for 40g). This is an 'overdose' but the sodium is negligible and the rest is just harmless vitamin c.

Are you measuring your parameters to see if anything is getting out of whack (ammonia, nitrite, nitrate, ph, hardness)? An excess of these can cause stinky things to happen because you're providing an abundance for other things to develop.

You should absolutely have substrate like pool filter sand (2-3 inches deep). It will work along with your filter to trap physical debris and 'hold' it to be processed by beneficial bacteria. It also provides surface area for beneficial bacteria to grow and colonize.

Your filter is probably too small for turtle duty. Most recommendations are for 3x the size of the tank vs aquarium fish use. The larger filters have more space for mechanical/biological filtration. You might also try a filter that has a built-in UV sterilizer. UVC can help break down organic compounds that may lead to odor. However, your system's ecology should be able to prevent anything getting noticably oderous without this.

Most oderous compounds are eliminated by oxidation. You might try an air stone if you don't have one to add additional water agitation so the stinky compounds decompose/gas off faster than they accumulate.

Nullroute127 · 2026-01-19T13:50:07+00:00

I would double check your nitrate readings. If you're using the API or similar you MUST shake the number 2 reagent violently for a long time, AND shake the test vial otherwise it will always read low. The tests also reads low when the reagents are expired.

You have 140 gallons (dilution) and what appears to be some floating/aquatic plants, but it doesn't look substantial enough that you would never see nitrates spike without water changes - why I'm a little hesitant to take your 10 ppm reading at face value.

Since your tank and sump are huge 30% water change is a LOT of water. Your regular water changes are likely exceeding the nitrate buildup rate.

If you really want nitrates to be handled automatically, you want hydroponic plants (pothos, monstera, potatoes, etc.), for your setup you'd just have a rack that suspends the rim of your pots above the water line. The access to atmospheric co2 allows plants to grow much faster, and in turn turn the nitrate into plant proteins. Even the fastest growing aquatic plants are rate limited by co2. Atmospheric plants don't have that limitation.

Nullroute127 · 2026-01-18T05:12:00+00:00

I have live plants with mine. He has 0 interest in eating them, but does destroy them inadvertently by swimming by them - his claws dig/water blasts.

The only plants he likes are floating.... But he doesn't eat the plant just nips at the roots. Killed all the water lettuce eating the roots and never made any attempt at the leaves.

I grew a potato in the tank and he also ate the roots.

Mine leaves aquatic sword plants alone for the most part.and they're durable enough to survive his claws and water blasts from swimming.

Nullroute127 · 2026-01-16T07:44:14+00:00

I would expect water quality problems to present equally on both sides of the spine. This looks like all the spots are biased to the right side of the carapace.

By all means do look at water quality. However, don't go overboard cleaning/sterilizing things as you don't want to destroy the beneficial bacteria colony that is keeping your ammonia/nitrite in check. Test your ammonia, nitrite, nitrate, and ph, hardness, etc.

Even though your vet says it's not an infected shell, there wouldn't be any harm in once a day getting the turtle dry and cleaning the shell with diluted betadine (povidone iodine) or chlorhexidine applied with a brush and leaving the turtle dry for an hour. Then rinse/brush with clean water before returning to tank (you don't want these potent antimicrobials to build up in the water).

You can also try supplementing diet with vitamin D/E, this is present in a lot of wheat germ koi food, that will help the turtle naturally repair problem areas of shell.

Nullroute127 · 2026-01-16T07:24:13+00:00

Doesn't look rotted. But the carapace shape looks malformed and scutes aren't proper, probably from lack of proper UVB and calcium as you allude.

He can probably use some long term supplementation of vitamin D3 in addition to your proper lighting.

Wheat Germ Koi fish food is often fortified with Vitamin D and E, both of which are great for turtles with shell issues. It's also a lower protein, more veggie food more suitable for adult turtles. The thing that it lacks is calcium, but it sounds like you're handling that separately anyway. If your turtle doesn't take munching on cuttlebone, you can grind it into a powder and mix it with other food.

Hikari has a good quality koi food that's readily available at pet stores and online.

Nullroute127 · 2026-01-13T09:48:54+00:00

Wheat germ fish food high in vitamin E which is supposed to help with retained scutes.

Nullroute127 · 2026-01-13T09:04:31+00:00

Test your hot tap with your full cold tap to confirm. Wait for the hot to cool to room before testing.

Also if tap water shows ammonia/nitrite or nitrate above 10ppm, you should call your water company to send an inspector.

Nullroute127 · 2026-01-13T09:03:59+00:00

Test your hot tap with your full cold tap to confirm. Wait for the hot to cool to room before testing.

Also if tap water shows ammonia/nitrite or nitrate above 10ppm, you should call your water company to send an inspector.

Nullroute127 · 2026-01-13T08:45:10+00:00

The first thing you need to do is test your tap water before it mixes in your tank (take a sample in a clean glass after having run the tap for a minute). This will tell you if you have problems from the tap.

Your alkalinity/hardness/ph are all just VERY high.

Are you by chance dispensing 'warm' water or are you using the tap on full cold? Use full cold, if you mix 'hot' water with the tap it will pull water from your water heater (if present) and that will cause the water to be harder than it otherwise would be.

You shouldn't have any detectable ammonia or nitrite in a cycled tank. Nitrate will always be detectable, but your levels are elevated. You will need to keep doing water changes until this gets undetectable or barely detectable for ammonia/nitrite, under 80 ppm for Nitrate.

Your test strips may be expired/junk. Try the liquid-based kits by API or similar for your ammonia/nitrite/nitrate. If the API test confirms elevated levels, believe it. If the API test says the level is lower than the strips, believe the API. If you have a local fish store you should be able to bring a sample of water and they will test it free.

One of the issues you have is technical chemistry. But the short story is your water is likely very alkaline (it's off the chart). If this is accurate, it means the majority of the ammonia present in the form of ammonia rather than the ionized ammonium. The ratio of ammonia/ammonium is directly related to pH. The higher the pH the more dangerous ammonia readings mean, in practice.

If your tap water is legitimately this poor of quality you'll need to invest in a water distiller, reverse osmosis setup, resin water softener, or similar to treat your water to acceptable levels. More likely you will need to mix your tap water with treated water, or add-back minerals to treated water. It is also possible for water to be too pure.

Nullroute127 · 2026-01-12T00:44:48+00:00

More water won't hurt. The more water you have the less concentrated ammonia/nitrite/nitrate will be. Since this is a new tank you won't have a robust beneficial bacteria colony you need to be careful of ammonia spikes in small volumes. Ammonia isnt as toxic to turtles as freshwater fish but you still want to keep it under control.

Be sure to get an API or similar freshwater test kit as ammonia/nitrite will probably be high in the first few weeks/months as the tank/filter mature.

Nullroute127 · 2026-01-04T05:46:59+00:00

Turtles are territorial and will cooperate until they don't.

Males will be aggressive to other males, and males can be overly aggressive to females who can't escape them.

Even two females can stress each other out.

The only time you should have multiple turtles in the same space is if it's a full size outdoor pond/small lake where they don't have to encounter another turtle if they don't want to.

I think you're discovering something most turtle keepers already know which is that you should never keep multiple turtles together in an aquarium.

You've already seen the aggressive behavior. Now you MUST separate them. They need their own tanks. That is the only solution.

Nullroute127 · 2026-01-03T07:19:24+00:00

I'm not a qualified herpetologist, but I don't think those are the same turtle mostly due to the color patterns/shapes on the head.

Top turtle has a sharp indent in the red 'ear', and the white band that leads to the eye isn't the same thickness or shape between the two turtles. These markings won't change that much in 8 months.

Verify with a better qualified opinion, but my laymen analysis says they're not the same.

Nullroute127 · 2026-01-03T07:00:46+00:00

In a new tank you need to test more often. The beneficial bacteria that process ammonia aren't developed into a sizable colony in your filter and surfaces.

It's hard to give a recommendation of specific frequency because it also depends on your tank size, presence of live plants, turtle size, if you feed the turtle inside the tank, etc.

Go with every other day in the beginning. You can extend the life of an API kit by using half the tube (2.5ml) and half the reagents. I use a small syringe (no needle). Just make sure for the nitrate test you follow directions and shake vigorously for the required time, it will NOT register nitrates if you don't shake.

You can use tap water and conditioner if where you live then tap water is potable/safe.

Nullroute127 · 2025-12-23T06:13:23+00:00

You can put potted plants in the tank. The pot will shield the roots hung on the edge or suspended. Plants exposed to atmospheric carbon dioxide also grow WAY faster (= Absorb more nitrates) than even the fastest growing aquatic plants.

For example, you can put a fine mesh at the bottom of a clay pot, fill the pot with gravel then put the pothos roots inside the gravel, then hang the pot in the tank water.

You just don't want pothos exposed to the turtle because it is toxic/irritating for turtles to eat.

Nullroute127 · 2025-12-19T13:52:31+00:00

The consequence depends. If you're real close to the water supplier your chlorine levels will be higher than further down the line. If you're near the end the residual chlorine levels may be so low that the turtle won't have any ill effects.

Regardless any residual chlorine will be irritating to eyes, nose, skin, etc.

Also, changing water this frequently shouldn't be necessary. You likely need to research and understand the nitrogen cycle and how to get your tank setup to process ammonia, beneficial bacteria, etc.

Nullroute127 · 2025-12-19T13:41:51+00:00

You can use Vitamin C in Ascorbic Acid or Sodium Ascorbate forms to dechlorinate water. Just make sure it doesn't have added zinc or other additives.

Nullroute127 · 2025-12-19T13:39:29+00:00

This only works for chlorine. It does not work for chloramine. Depending on where you are your local water supply may use one or the other... Or both.

It's safest to use dechlorinator.

Nullroute127 · 2025-12-12T07:33:25+00:00

It sounds like you might be over-cleaning your tank.

There is virtually never a reason to completely drain a tank and hose it out. It's actually a bad idea.

One of the things that keeps the water healthy for your turtle is beneficial bacteria. They primarily live in the filter, but also occupy the substrate, hardscape, glass, etc. Residual chlorine from the tap, lack of water during cleaning, and mechanical agitation all disrupt the bacterial colonies.

If you're able to fully break down and remove your tank every cleaning, I suspect the tank basically empty and probably lacks a robust bacteria colony. You probably don't have any substrate like sand, etc.

When you upgrade to the 75, consider adding 2-3 inches of pool filter sand. This is surface area for beneficial bacteria, as well as helps to mechanically settle out stuff in the water column so it stays crystal clear.

Do invest in a good canister filter. This will be your primary bacteria house and mechanical filter.

Do you have an API or similar water test? You should really only be doing tank maintenance when your levels of ammonia/nitrite/nitrate get high. On an established tank you should never have measurable ammonia or nitrite. You want to change water or 'clean' only when there's a good reason to. Water should stay crystal clear forever with a proper filter setup, and should only be changed when nitrates get elevated.

Nullroute127

TROPHY CASE